CN110337499A

CN110337499A - The manufacturing method of high-strength simple-cutting copper alloy and high-strength simple-cutting copper alloy

Info

Publication number: CN110337499A
Application number: CN201880013551.8A
Authority: CN
Inventors: 大石惠一郎; 须崎孝一; 后藤弘树
Original assignee: Mitsubishi Shindoh Co Ltd
Current assignee: Mitsubishi Shindoh Co Ltd
Priority date: 2016-08-15
Filing date: 2018-02-21
Publication date: 2019-10-15
Anticipated expiration: 2038-02-21
Also published as: JPWO2018034281A1; KR20190018534A; JP6391205B2; TW201812036A; KR20190018540A; KR101991227B1; TWI657155B; TW201910527A; CN110337499B; CN110249065A; JPWO2018034282A1; KR102021724B1; WO2018034282A1; TW201812037A; CN109563569A; TWI636145B; US20190256960A1; US11313013B2; CN110268077B; TW201812038A

Abstract

The present invention provides a kind of high-strength simple-cutting copper alloy, the high-strength simple-cutting copper alloy contains Cu:75.4~78.0%, Si:3.05~3.55%, P:0.05~0.13%, and Pb:0.005~0.070%, and remainder includes Zn and inevitable impurity, as inevitable impurity, existing Sn amount is 0.05% or less, Al amount is 0.05% or less, the total amount of Sn and Al is 0.06% or less, composition meets following relationship: 78.0≤f1=Cu+0.8 × Si+P+Pb≤80.8, 60.2≤f2=Cu-4.7 × Si-P+0.5 × Pb≤61.5, the area ratio (%) for constituting phase meets following relationship: 29≤κ≤60, 0 ≤ γ≤0.3, β=0,0≤μ≤1.0,98.6≤f3=α+κ, 99.7≤f4=α+κ+γ+μ ,+μ≤1.2 0≤f5=γ ,+6 × γ of 30≤f6=κ^1/2The long side of+0.5 × μ≤62, γ phase is 25 μm hereinafter, the long side of μ phase is 20 μm hereinafter, there are κ phases in α phase.

Description

The manufacturing method of high-strength simple-cutting copper alloy and high-strength simple-cutting copper alloy

Technical field

Have high intensity, elevated temperature strength, excellent ductility and impact characteristics and good corrosion resistant the present invention relates to a kind of Corrosion and be greatly decreased lead content high-strength simple-cutting copper alloy and high-strength simple-cutting copper alloy manufacturer Method.More particularly to a kind of valve used under various adverse circumstances, connector, pressure vessel etc. it is electrical/automobile/machinery/industrial Piping, container relevant to hydrogen, valve, connector and for the high-strength of utensil used in the drinking water such as tap, valve, connector Spend the manufacturing method of free-cutting machinability copper alloy and high-strength simple-cutting copper alloy

The application is based on International Application Serial No. PCT/JP2017/29369, PCT/JP2017/ filed on August 15th, 2017 29371, PCT/JP2017/29373, PCT/JP2017/29374, PCT/JP2017/29376 CLAIM OF PRIORITY, and by its content It is applied at this.

Background technique

All the time, including the utensil class of drinking water, as being used in the electric gas vapor such as valve, connector, pressure vessel Vehicle/machinery/industrial piping copper alloy, generally uses the Pb and residue of the Cu containing 56~65 mass % and 1~4 mass % Part is set as the Cu-Zn-Pb alloy (so-called free-cutting brass) of Zn or Cu containing 80~88 mass %, 2~8 mass % The Pb of Sn and 2~8 mass % and remainder are set as the Cu-Sn-Zn-Pb alloy (so-called bronze: Gun copper) of Zn.

However, influence of the Pb to human body and environment in recent years becomes another people's worry, various countries are more living to the limitation campaign of Pb Jump.For example, California, USA from January, 2010 and in the whole America from January, 2014, about by drinking water Pb content contained in utensil etc. is set as 0.25 mass % limitation below and has come into force.In the near future, if it is considered that baby The influence of child etc., it is stated that will limit to 0.05 mass % or so.In countries other than US, limitation movement is also quickly sent out Exhibition, thus it requires developing the Cu alloy material of the limitation of reply Pb content.

ELV also, in other industrial fields, automobile, mechanically and electrically/field of electronic device, such as in Europe refers to Enable, the Pb content of free-cutting machinability copper alloy exceptionally reaches 4 mass % in RoHS instruction, but identical as drinking water field, just In the positive limitation enhancing that the related Pb content including eliminating exception is discussed.

Advocated in the Pb limitation enhancing trend of this free-cutting machinability copper alloy be there is cutting sexual function and containing Bi and The copper alloy of Se improves the copper alloy of machinability and the Zn containing high concentration by increasing β phase in alloy of the Cu with Zn Deng to replace Pb.

It is insufficient come corrosion resistance if replacing Pb if only containing Bi for example, proposed in patent document 1, in order to reduce β phase And β phase is isolated, the hot extrusion pressure bar slow cooling after hot extrusion is implemented to be heat-treated in turn to becoming 180 DEG C.

Also, in patent document 2, Cu- is precipitated by adding the Sn of 0.7~2.5 mass % into Cu-Zn-Bi alloy The γ phase of Zn-Sn alloy, so as to improve corrosion resistance.

However, as shown in Patent Document 1, the alloy of Pb is replaced containing Bi, and there are problems in terms of corrosion resistance.Moreover, Bi have include may be harmful to the human body identically as Pb, due to be rare metal and in resource there are problem, copper can be made to close Many problems including the problem of golden material becomes fragile etc..In addition, as proposed in patent document 1,2, even if passing through heat Slow cooling or heat treatment after extrusion keep the β phase isolated to improve corrosion resistance, cannot achieve eventually in the presence of a harsh environment Corrosion resistance improvement.

Also, as shown in patent document 2, even if the γ phase of Cu-Zn-Sn alloy is precipitated, compared with α phase, the γ phase is original With regard to lacking corrosion resistance, to cannot achieve the improvement of corrosion resistance in the presence of a harsh environment eventually.Also, it is closed in Cu-Zn-Sn Jin Zhong, the cutting sexual function difference of the γ phase containing Sn are added to needs and together with the Bi with cutting sexual function.

On the other hand, for the copper alloy of the Zn containing high concentration, compared with Pb, the cutting sexual function of β phase is poor, therefore The free-cutting machinability copper alloy containing Pb, but also the especially resistance to dezincification of corrosion resistance due to comprising many β phases can not be not only replaced eventually Corrosivity, anticorrosion stress-resistant disruptiveness are excessively poor.Also, these copper alloys due to intensity is low, especially in high temperature (for example, about 150 DEG C) under intensity it is low, therefore for example under burning sun and close to engine room at a high temperature of use automobile component, in high temperature/height Depress can not be coped in the valve that uses and piping etc. be thinning, lightweight.In addition, for example in the pressure vessel of High Pressure Hydrogen, valve, match Tensile strength is low in pipe, therefore can only use under normal pressure.

In addition, Bi makes copper alloy become fragile, the ductility reduction if comprising many β phases, therefore copper alloy or packet containing Bi Copper alloy containing many β phases is not suitable as automobile, machinery, electrically with component and the drinking water utensil material including valve Material.In addition, be also unable to improve stress-corrosion cracking for the brass containing Sn and comprising γ phase in Cu-Zn alloy, in room temperature and Intensity under high temperature is low, and impact characteristics are poor, therefore is not suitable for being used in these on the way.

On the other hand, as the Cu- for proposing to replace Pb containing Si in free-cutting machinability copper alloy, such as patent document 3~9 Zn-Si alloy.

In patent document 3,4, by cutting sexual function mainly excellent with γ phase, thus by not containing Pb or containing There is a small amount of Pb to realize excellent machinability.By the Sn containing 0.3 mass % or more, increases and promote that there is cutting sexual function γ phase formation, so as to improve machinability.It is corrosion-resistant to improve by forming many γ phases also, in patent document 3,4 Property.

Also, in patent document 5, it is set as by containing 0.02 mass % minimal amount of Pb below, and mainly consider Pb content simultaneously simply specifies that γ phase, the total of κ phase contain area, to obtain excellent free-cutting machinability.Herein, Sn is acted on It is formed and increases γ phase, so as to improve erosion resistance corrosivity.

In addition, the cast product of Cu-Zn-Si alloy is proposed in patent document 6,7, in order to realize the fine of casting crystalline grain Change, P and Zr containing denier, and payes attention to the ratio etc. of P/Zr.

Also, it proposes to contain the copper alloy of Fe in Cu-Zn-Si alloy in patent document 8.

In addition, proposing to contain the copper alloy of Sn, Fe, Co, Ni, Mn in Cu-Zn-Si alloy in patent document 9.

Herein, as recorded in patent document 10 and non-patent literature 1, it is known that in above-mentioned Cu-Zn-Si alloy, even if It is 60 mass % or more that composition, which is limited in Cu concentration, and Zn concentration is 30 mass % hereinafter, Si concentration is 10 mass % hereinafter, removing Other than base (matrix) α phase, there is also β phase, γ phase, δ phase, ε phase, ζ phase, η phase, κ phase, μ phase, χ phase this 10 kinds of metal phase, According to circumstances there is also 13 kinds of metal phases for including α ', β ', γ '.In addition, rule of thumb it is well known that if increasing addition Element, then metallographic structure becomes more complicated, it is possible that new phase and intermetallic compound, also, by equilibrium state diagram In the alloy of obtained alloy and actual production, relatively large deviation can be generated in the composition of existing metal phase.In addition, many institutes These known phases composition also according to the concentration of Cu, Zn, Si of copper alloy etc. and processing thermal history (thermal history) and It changes.

But although γ phase has excellent cutting ability, since Si concentration is high and hard and crisp, if including many γ Phase, then can intensity under corrosion resistance in the presence of a harsh environment, ductility, impact characteristics, elevated temperature strength (high-temerature creep), room temperature And it is led to the problem of in cold-workability.Therefore, for the Cu-Zn-Si alloy comprising a large amount of γ phases, also with the copper alloy containing Bi or Copper alloy comprising many β phases is in the same manner at it using being above restricted.

In addition, documented Cu-Zn-Si alloy is in the Dezincification corrosion test based on ISO-6509 in patent document 3~7 Show relatively better result.However, in the Dezincification corrosion test based on ISO-6509, in order to determine in general water quality Dezincification corrosion resistant it is good whether, using the chlorination copper reagent entirely different with practical water quality, only with 24 hours, this was short Time is evaluated.That is, being evaluated using the reagent different from actual environment with the short time, therefore fails sufficiently to evaluate and dislike Corrosion resistance under bad environment.

Also, the case where containing Fe in Cu-Zn-Si alloy is proposed in patent document 8.But γ is compared in Fe and Si formation The intermetallic compound of mutually hard and crisp Fe-Si.The intermetallic compound there are it is following the problems such as: shorten in machining and cut The service life for cutting tool forms hard spot in polishing and generates apparent unfavorable condition.Also, using the Si of addition element as gold Compound between category and consumed, so as to cause alloy performance decline.

In addition, although being added to Sn and Fe, Co, Mn in Cu-Zn-Si alloy, Fe, Co, Mn are equal in patent document 9 Chemical combination is carried out with Si and generates hard and crisp intermetallic compound.Therefore, it is produced identically as patent document 8 in cutting and polishing Raw problem.In addition, by forming β phase containing Sn, Mn, but β phase causes serious Dezincification corrosion according to patent document 9, thus Improve the sensitivity of stress-corrosion cracking.

Patent document 1: Japanese Unexamined Patent Publication 2008-214760 bulletin

Patent document 2: International Publication No. 2008/081947

Patent document 3: Japanese Unexamined Patent Publication 2000-119775 bulletin

Patent document 4: Japanese Unexamined Patent Publication 2000-119774 bulletin

Patent document 5: International Publication No. 2007/034571

Patent document 6: International Publication No. 2006/016442

Patent document 7: International Publication No. 2006/016624

Patent document 8: Japanese Unexamined Patent Application Publication 2016-511792 bulletin

Patent document 9: Japanese Unexamined Patent Publication 2004-263301 bulletin

Patent document 10: U.S. Patent No. 4,055,445

Patent document 11: International Publication No. 2012/057055

Patent document 12: Japanese Unexamined Patent Publication 2013-104071 bulletin

Non-patent literature 1: beautiful Ma Yuanci youth, Hasegawa normal treatment: copper and brass technical research periodical, 2 (1963), 62~77 Page

Summary of the invention

The present invention completes to solve such prior art problem, and project is to provide under a kind of room temperature and high temperature Excellent strength and have excellent impact characteristics and ductility, and the good high strength easy of corrosion resistance in the presence of a harsh environment The manufacturing method of machinability copper alloy and high-strength simple-cutting copper alloy.In addition, in this specification, it is unless otherwise indicated, resistance to Corrosivity refers to both Dezincification corrosion resistant, anticorrosion stress-resistant disruptiveness.Also, hot-working material refer to hot extrusion material, Hot forged material, hot calender material.Cold-workability refers to the processability carried out under the cold conditions such as riveting, bending.Hot properties refers to about High-temerature creep, tensile strength under 150 DEG C (100 DEG C~250 DEG C).Cooling velocity refers to average cold in a certain temperature range But speed.

The purpose, the high-strength simple-cutting copper alloy of the 1st mode of the invention are realized in order to solve this project It is characterized in that, contains 75.4 mass % or more and 78.0 mass % Cu below, 3.05 mass % or more and 3.55 mass % Si, 0.05 mass % or more and 0.13 mass % P below and 0.005 mass % or more below and 0.070 mass % or less Pb, and remainder includes Zn and inevitable impurity,

As inevitable impurity, the content of existing Sn is 0.05 mass % or less, the content of Al is 0.05 matter Measure % hereinafter, Sn and Al total content be 0.06 mass % hereinafter,

The content of Cu is set as [Cu] quality %, the content of Si is set as to [Si] quality %, the content of Pb is set as [Pb] Quality %, when the content of P to be set as to [P] quality %, there is following relationship:

78.0≤f1=[Cu]+0.8 × [Si]+[P]+[Pb]≤80.8,

60.2≤f2=[Cu] -4.7 × [Si]-[P]+0.5 × [Pb]≤61.5,

Also, in the composition phase of metallographic structure, the area ratio of α phase is set as (α) %, is set as the area ratio of β phase (β) %, the area ratio of γ phase is set as (γ) %, the area ratio of κ phase is set as to (κ) %, the area ratio of μ phase is set as to (μ) % When, there is following relationship:

29≤(κ)≤60、

0≤(γ)≤0.3、

(β)=0,

0≤(μ)≤1.0、

98.6≤f3=(α)+(κ),

99.7≤f4=(α)+(κ)+(γ)+(μ),

0≤f5=(γ)+(μ)≤1.2,

30≤f6=(κ)+6 × (γ)^1/2+ 0.5 × (μ)≤62,

Also, the length of the long side of γ phase is 25 μm hereinafter, the length of the long side of μ phase is 20 μm hereinafter, there are κ in α phase Phase.

The high-strength simple-cutting copper alloy of 2nd mode of the invention is characterized in that, in the height of the 1st mode of the invention In intensity free-cutting machinability copper alloy, also containing selected from 0.01 mass % or more and 0.07 mass % Sb below, 0.02 mass % Above and 0.07 mass % As below and 0.005 mass % or more and 0.10 mass % Bi below it is one or two kinds of with On.

The high-strength simple-cutting copper alloy of 3rd mode of the invention is characterized in that, containing 75.6 mass % or more and 77.8 mass % Cu below, 3.15 mass % or more and 3.5 mass % Si below, 0.06 mass % or more and 0.12 matter Measure % P and 0.006 mass % or more below and 0.045 mass % Pb below, and remainder includes Zn and inevitable Impurity,

As inevitable impurity, the content of existing Sn is 0.03 mass % or less, the content of Al is 0.03 matter Measure % or less, the total content of Sn and Al are 0.04 mass % hereinafter,

78.5≤f1=[Cu]+0.8 × [Si]+[P]+[Pb]≤80.5,

60.4≤f2=[Cu] -4.7 × [Si]-[P]+0.5 × [Pb]≤61.3,

33≤(κ)≤58、

(γ)=0,

(β)=0,

0≤(μ)≤0.5、

99.3≤f3=(α)+(κ),

99.8≤f4=(α)+(κ)+(γ)+(μ),

0≤f5=(γ)+(μ)≤0.5,

33≤f6=(κ)+6 × (γ)^1/2+ 0.5 × (μ)≤58,

Also, there are κ phase in α phase, the length of the long side of μ phase is 15 μm or less.

The high-strength simple-cutting copper alloy of 4th mode of the invention is characterized in that, in the height of the 3rd mode of the invention In intensity free-cutting machinability copper alloy, also containing selected from 0.012 mass % or more and 0.05 mass % Sb below, 0.025 matter Measure the one or two of % or more and 0.05 mass % As below and 0.006 mass % or more and 0.05 mass % Bi below More than, and the total content of Sb, As and Bi are 0.09 mass % or less.

The high-strength simple-cutting copper alloy of 5th mode of the invention is characterized in that, in the 1st~4 mode of the invention In the high-strength simple-cutting copper alloy of middle either type, the total amount of Fe, Mn, Co and Cr as the inevitable impurity Less than 0.08 mass %.

The high-strength simple-cutting copper alloy of 6th mode of the invention is characterized in that, in the 1st~5 mode of the invention In the high-strength simple-cutting copper alloy of middle either type, the Charpy-type test value of U-shaped recess shape is 12J/cm²Above and 50J/cm²Hereinafter, the tensile strength under room temperature is 550N/mm²More than, and have 0.2% surrender quite at room temperature in load Creep strain after being kept for 100 hours at 150 DEG C in the state of the load of intensity is 0.3% or less.

In addition, Charpy-type test value is the value in the test piece of U-shaped recess shape.

The high-strength simple-cutting copper alloy of 7th mode of the invention is characterized in that, in the 1st~5 mode of the invention In the high-strength simple-cutting copper alloy of middle either type, which is hot-working material, and tension is strong Spend S (N/mm²) it is 550N/mm²More than, elongation E (%) is 12% or more, the Charpy-type test value I (J/ of U-shaped recess shape cm²) it is 12J/cm²More than, and

675≤f8=S × { (E+100)/100 }^1/2Or

700≤f9=S × { (E+100)/100 }^1/2+I。

The high-strength simple-cutting copper alloy of 8th mode of the invention is characterized in that, in the 1st~7 mode of the invention In the high-strength simple-cutting copper alloy of middle either type, it is used in running water pipe utensil, industrial piping-member and liquid In body or utensil, pressure vessel and the connector of gas contact, automotive part or electric product component.

The manufacturing method of the high-strength simple-cutting copper alloy of 9th mode of the invention is characterized in that, the manufacturing method For the manufacturing method of the high-strength simple-cutting copper alloy of either type in the 1st~8 mode of the invention,

Include any one in cold working process and hot procedure or both；And in the cold working process or The annealing operation implemented after the hot procedure,

In the annealing operation, copper alloy is heated under either condition in following (1)~(4), is cooled down,

(1) it is kept for 15 minutes to 8 hours under 525 DEG C or more and 575 DEG C of temperature below, or

(2) at 505 DEG C more than and less than 525 DEG C at a temperature of keep 100 minutes to 8 hours, or

(3) maximum temperature reached is 525 DEG C or more and 620 DEG C hereinafter, and protecting 575 DEG C to 525 DEG C of temperature region It holds 15 minutes or more, or

(4) by 575 DEG C to 525 DEG C of temperature region with 0.1 DEG C/min or more and 3 DEG C/min average cooling speed below Degree is cooled down,

It is above-mentioned copper alloy is heated, is cooled down after, by 450 DEG C to 400 DEG C of temperature region with 3 DEG C/min with Upper and 500 DEG C/min of average cooling rates below are cooled down.

The manufacturing method of the high-strength simple-cutting copper alloy of 10th mode of the invention is the 1st~6 mode of the invention The manufacturing method of the high-strength simple-cutting copper alloy of middle either type,

The method comprising: casting process；And the annealing operation implemented after the casting process,

The manufacturing method of the high-strength simple-cutting copper alloy of 11st mode of the invention is characterized in that, the manufacturing method For the manufacturing method of the high-strength simple-cutting copper alloy of either type in the 1st~8 mode of the invention,

Including hot procedure,

Carry out hot-working when material temperature be 600 DEG C or more and 740 DEG C hereinafter,

In cooling procedure after thermoplasticity processing, by 575 DEG C to 525 DEG C of temperature region with 0.1 DEG C/min or more and 3 DEG C/min of average cooling rates below are cooled down, by 450 DEG C to 400 DEG C of temperature region with 3 DEG C/min or more and 500 DEG C/min of average cooling rates below are cooled down.

The manufacturing method of the high-strength simple-cutting copper alloy of 12nd mode of the invention is characterized in that, the manufacturing method For the manufacturing method of the high-strength simple-cutting copper alloy of either type in the 1st~8 mode of the invention,

Include any one in cold working process and hot procedure or both；And in the cold working process or The low-temperature annealing process implemented after the hot procedure,

In the low-temperature annealing process, material temperature is set as 240 DEG C or more and 350 DEG C ranges below, will heating Time is set as 10 minutes or more and 300 minutes ranges below, material temperature is set as T DEG C, will be set as heating time t minutes When, it is set as 150≤(T-220) × (t)^1/2≤ 1200 condition.

Mode according to the present invention, it is specified that strongly reduce or eliminate and (be free of) excellent cutting sexual function but corrosion resistance, Ductility, impact characteristics, elevated temperature strength (high-temerature creep) difference γ phase, and as far as possible reduce or be free of μ effective to machinability Phase, and exist in α phase to metallographic structure made of intensity, machinability, the effective κ phase of corrosion resistance.It alsies specify and is used for Composition, manufacturing method to the metallographic structure.Therefore, mode according to the present invention is capable of providing the strong of a kind of room temperature and high temperature Spend the height of the cold-workabilities and excellent corrosion resistance such as height, impact characteristics, ductility, abrasion performance, voltage endurance, riveting or bending The manufacturing method of intensity free-cutting machinability copper alloy and high-strength simple-cutting copper alloy.

Detailed description of the invention

Fig. 1 is the electron micrograph of the tissue of the high-strength simple-cutting copper alloy (test No.T05) in embodiment 1.

Fig. 2 is the metallic micrograph of the tissue of the high-strength simple-cutting copper alloy (test No.T73) in embodiment 1.

Fig. 3 is the electron micrograph of the tissue of the high-strength simple-cutting copper alloy (test No.T73) in embodiment 1.

Specific embodiment

Hereinafter, high-strength simple-cutting copper alloy and high-strength simple-cutting copper alloy to embodiments of the present invention Manufacturing method is illustrated.

The high-strength simple-cutting copper alloy of present embodiment as valve, connector, slide unit etc. it is electrical/automobile/machinery/ Industrial piping-member, the utensil for being contacted with liquid or gas, component, pressure vessel and connector, tap, valve, connector Deng the drinking water in the every daily ingestion of people utensil and use.

Herein, in the present specification, as [Zn] this element mark with parantheses is set as indicating the content (matter of the element Measure %).

Moreover, providing multiple component relationship formulas as follows using the representation method of the content in present embodiment.

Component relationship formula f1=[Cu]+0.8 × [Si]+[P]+[Pb]

Component relationship formula f2=[Cu] -4.7 × [Si]-[P]+0.5 × [Pb]

In addition, being set as follows in the composition phase of metallographic structure in present embodiment, that is, indicate the face of α phase with (α) % Product rate, the area ratio of β phase is indicated with (β) %, and the area ratio of γ phase is indicated with (γ) %, and the area ratio of κ phase is indicated with (κ) %, The area ratio of μ phase is indicated with (μ) %.In addition, the composition of metallographic structure mutually refers to that α phase, γ phase, κ are equal, and metal is not contained Between compound, precipitate, non-metallic inclusion etc..Also, the κ phase being present in α phase is contained in the area ratio of α phase.It is all The sum for constituting the area ratio of phase is set as 100%.

Moreover, providing multiple membership credentials formulas as follows in present embodiment.

Membership credentials formula f3=(α)+(κ)

Membership credentials formula f4=(α)+(κ)+(γ)+(μ)

Membership credentials formula f5=(γ)+(μ)

Membership credentials formula f6=(κ)+6 × (γ)^1/2+0.5×(μ)

The high-strength simple-cutting copper alloy of 1st embodiment of the invention contains 75.4 mass % or more and 78.0 matter Measure % Cu below, 3.05 mass % or more and 3.55 mass % Si below, 0.05 mass % or more and 0.13 mass % with Under P and 0.005 mass % or more and 0.070 mass % Pb below, and remainder includes Zn and inevitable impurity. As inevitable impurity, the content of existing Sn is 0.05 mass % or less, the content of Al is 0.05 mass % hereinafter, And the total content of Sn and Al is 0.06 mass % hereinafter, component relationship formula f1 is located in the range of 78.0≤f1≤80.8, Component relationship formula f2 is located in the range of 60.2≤f2≤61.5.The area ratio of κ phase is located in the range of 29≤(κ)≤60, γ The area ratio of phase is located in the range of 0≤(γ)≤0.3, and the area ratio of β phase is set as 0 ((β)=0), and the area ratio of μ phase is located at 0 In the range of≤(μ)≤1.0.Membership credentials formula f3 is set as 98.6≤f3, and membership credentials formula f4 is set as 99.7≤f4, membership credentials Formula f5 is located in the range of 0≤f5≤1.2, and membership credentials formula f6 is located in the range of 30≤f6≤62.The length of the long side of γ phase Degree is for 25 μm hereinafter, the length of the long side of μ phase is set as 20 μm hereinafter, there are κ phases in α phase.

The high-strength simple-cutting copper alloy of 2nd embodiment of the invention contains 75.6 mass % or more and 77.8 matter Measure % Cu below, 3.15 mass % or more and 3.5 mass % Si below, 0.06 mass % or more and 0.12 mass % or less P and 0.006 mass % or more and 0.045 mass % Pb below, and remainder includes Zn and inevitable impurity.Make For inevitable impurity, the content of existing Sn is 0.03 mass % or less, the content of Al is 0.03 mass % hereinafter, simultaneously And the total content of Sn and Al is 0.04 mass % or less.Component relationship formula f1 is located in the range of 78.5≤f1≤80.5, group It is located in the range of 60.4≤f2≤61.3 at relational expression f2.The area ratio of κ phase is located in the range of 33≤(κ)≤58, γ phase It is set as 0 ((γ)=0, (β)=0) with the area ratio of β phase, the area ratio of μ phase is located in the range of 0≤(μ)≤0.5.Tissue closes It is that formula f3 is set as 99.3≤f3, membership credentials formula f4 is set as 99.8≤f4, and membership credentials formula f5 is located at the range of 0≤f5≤0.5 Interior, membership credentials formula f6 is located in the range of 33≤f6≤58.There are κ phase in α phase, the length of the long side of μ phase be set as 15 μm with Under.

It, can be also containing selected from 0.01 matter also, in the high-strength simple-cutting copper alloy of the 1st embodiment of the invention Amount % or more and 0.07 mass % Sb below, 0.02 mass % or more and 0.07 mass % As below and 0.005 mass % Above and the one or more of 0.10 mass % Bi below.

It, can be also containing selected from 0.012 also, in the high-strength simple-cutting copper alloy of the 2nd embodiment of the invention Quality % or more and 0.05 mass % Sb below, 0.025 mass % or more and 0.05 mass % As below, 0.006 matter The one or more of % or more and 0.05 mass % Bi below are measured, the total content of Sb, As and Bi are 0.09 mass % Below.

In of the invention 1st, 2 embodiments high-strength simple-cutting copper alloys, as inevitable impurity Fe, The total amount of Mn, Co and Cr are preferably less than 0.08 mass %.

Also, the of the invention 1st, in the high-strength simple-cutting copper alloy of 2 embodiments, preferred U-shaped recess shape Charpy-type test value is 12J/cm²More than and less than 50J/cm², the tensile strength under room temperature (room temperature) is 550N/mm²More than, And by copper alloy in the state that load has 0.2% yield strength (load for being equivalent to 0.2% yield strength) at room temperature Creep strain after being kept for 100 hours at 150 DEG C is 0.3% or less.

It is of the invention 1st, 2 embodiments via hot worked high-strength simple-cutting copper alloy (hot-working material) In, preferably with tensile strength S (N/mm²), elongation E (%), Charpy-type test value I (J/cm²) between relationship in, resist Tensile strength S is 550N/mm²More than, elongation E is 12% or more, and the Charpy-type test value I of U-shaped recess shape is 12J/cm² More than, and f8=S × { (E+ as tensile strength (S) and the product of 1/2 power of { (elongation (E)+100)/100 } 100)/100}^1/2Value be 675 or more, or as f8 and I's and f9=S × { (E+100)/100 }^1/2The value of+I is 700 More than.

Hereinafter, to composition requirement relational expression f1, f2 as described above, metallographic structure, membership credentials formula f3, f4, f5, f6 with And the reasons why mechanical property, is illustrated.

< is at being grouped as >

(Cu)

Cu is that the essential element of the alloy of present embodiment needs at least to contain 75.4 to overcome project of the invention The Cu of the amount of quality % or more.When Cu content is less than 75.4 mass %, although according to the content of Si, Zn, Sn, Pb, manufacturing process And it is different, but ratio shared by γ phase is more than 0.3%, corrosion resistance, impact characteristics, ductility, normal temperature strength and hot properties (high-temerature creep) is poor.In some cases, it also will appear β phase sometimes.Therefore, the lower limit of Cu content is 75.4 mass % or more, Preferably 75.6 mass % or more, more preferably 75.8 mass % or more, most preferably 76.0 mass % or more.

On the other hand, if Cu content is more than 78.0 mass %, not only to corrosion resistance, normal temperature strength and elevated temperature strength Effect is saturated and γ phase is reduced, but ratio shared by κ phase may also become excessive.Also, it is easy that the highly concentrated μ of Cu is precipitated Phase, or be easy that ζ phase, χ phase is precipitated in some cases.Although may lead as a result, different according to the important document of metallographic structure Machinability, ductility, impact characteristics, hot-workability is caused to be deteriorated.Therefore, the upper limit of Cu content be 78.0 mass % hereinafter, it is preferred that It is 77.5 mass % hereinafter, further preferably 77.3 matter for 77.8 mass % hereinafter, when paying attention to ductility and impact characteristics Measure % or less.

(Si)

Si is many excellent characteristics of the alloy of present embodiment in order to obtain and required element.Si is contributed to form κ phase, γ phase, μ phase, β phase, the equal metal phase of ζ.Si improves machinability, corrosion resistance, the intensity, height of the alloy of present embodiment Temperature characteristics and abrasion performance.About machinability, in the case where α phase, hardly improve machinability containing Si.But It is, due to γ phase, κ phase, the equal phase harder than α phase of μ formed and containing Si, even if not containing a large amount of Pb, also can Enough there is excellent machinability.However, ductility, impact can be generated as ratio shared by γ phase or the equal metal phase of μ increases The problem of corrosion resistance under the problem of characteristic, cold-workability decline, adverse circumstances declines, and can bear to be used for a long time Hot properties on lead to the problem of.κ is opposite to improve machinability and intensity is useful, but if κ phase is excessive, then ductility, rush Characteristic, processability decline are hit, machinability is also deteriorated in some cases.Therefore, it is necessary to provide κ phase, γ phase, μ phase, β phase In appropriate range.

Also, Si has the effect of substantially inhibiting the evaporation of Zn when melting, casting, and then with increase Si content, energy Enough reduce specific gravity.

In order to solve the problems, such as these metallographic structures and meet all various characteristics, although according to the content of Cu, Zn etc. Difference, but Si is needed containing 3.05 mass % or more.The lower limit of Si content is preferably 3.1 mass % or more, and more preferably 3.15 Quality % or more, further preferably 3.2 mass % or more.Especially when paying attention to intensity, preferably 3.25 mass % or more.Table On face, in order to reduce ratio shared by the highly concentrated γ phase of Si and μ phase, it is believed that Si content should be reduced.But have extensively studied with The mix proportions of other elements and manufacturing process as a result, it is desirable to it is as described above regulation Si content lower limit.Although also, very Content, component relationship formula f1, f2 and the manufacturing process of other elements are depended in big degree, but with about 3.0 mass % of Si content For boundary, α phase is interior by the elongated needle-shaped κ phase that comes into existence, and using about 3.15 mass % of Si content as boundary, the amount of needle-shaped κ phase is further Increase, if Si content reaches about 3.25 mass %, the presence of needle-shaped κ phase becomes obvious.It is present in the κ phase in α phase by this, It does not damage ductility and improves machinability, tensile strength, hot properties, impact characteristics, abrasion performance.Hereinafter, also will be present in α κ phase in phase is known as 1 phase of κ.

On the other hand, if Si content is excessive, κ, which meets, becomes excessive.1 phase of κ existed simultaneously in α phase also became It is more.If κ phase becomes excessively, since κ phase is originally just than the poor ductility of α phase and hard, ductility, impact spy in alloy Property, become problem in terms of machinability.Also, if 1 phase of κ becomes excessively, and ductility possessed by α phase itself is impaired, as conjunction The ductility reduction of gold.In present embodiment, be mainly focused on it is high-intensitive have both together good ductility (elongation) and The case where impact characteristics, thus the upper limit of Si content be 3.55 mass % hereinafter, preferably 3.5 mass % hereinafter, in particular, if Pay attention to the cold-workability of ductility or impact characteristics, riveting etc., then more preferably 3.45 mass % are hereinafter, further preferably 3.4 mass % or less.

(Zn)

Zn and Cu, Si mono- are all the main composition element of the alloy of present embodiment, are to improve machinability, corrosion-resistant Element needed for property, intensity, castability.Although, but if insisting on recording, Zn contains in addition, Zn exists as remainder The upper limit of amount is about 21.5 mass % hereinafter, lower limit is about 17.5 mass % or more.

(Pb)

The machinability of copper alloy can be improved containing Pb.The Pb of about 0.003 mass % melts in base admittedly, more than the Pb of the amount Exist as 1 μm of diameter or so of Pb particle.Even micro Pb, it is also effective to machinability, thus with 0.005 mass % Above content starts to play effect.In the alloy of present embodiment, since the excellent γ phase of cutting ability is suppressed to 0.3% Hereinafter, therefore a small amount of Pb replaces γ phase.The lower limit of the content of Pb is preferably 0.006 mass % or more.

On the other hand, Pb is harmful to the human body, also related with composition and metallographic structure, but to ductility, impact characteristics, room temperature And elevated temperature strength and cold-workability have an impact.Therefore, the upper limit of the content of Pb is 0.070 mass % hereinafter, preferably 0.045 matter % is measured hereinafter, if it is considered that influence to human body and environment, then most preferably less than 0.020 mass %.

(P)

P greatly improves the corrosion resistance under adverse circumstances.Meanwhile containing a small amount of P, machinability can be improved, and improve Tensile strength and ductility.

In order to play these effects, the lower limit of P content is 0.05 mass % or more, preferably 0.055 mass % or more, more Preferably 0.06 mass % or more.

On the other hand, if containing the P for having more than 0.13 mass %, the not only effect saturation of corrosion resistance, but also impact Characteristic, ductility and cold-workability are also sharply deteriorated, and machinability is also deteriorated instead.Therefore, the upper limit of P content is 0.13 mass % Hereinafter, preferably 0.12 mass % is hereinafter, more preferably 0.115 mass % or less.

(Sb、As、Bi)

Sb, As further increase Dezincification corrosion resistant especially in the presence of a harsh environment identically as P, Sn.

In order to need preferably to contain containing the Sb of 0.01 mass % or more by improving corrosion resistance containing Sb The Sb of 0.012 mass % or more.On the other hand, even if containing the Sb for having more than 0.07 mass %, the effect of corrosion resistance raising It can be saturated, γ phase increases instead, therefore the content of Sb is 0.07 mass % hereinafter, preferably 0.05 mass % or less.

Also, in order to need preferably to contain containing the As of 0.02 mass % or more by improving corrosion resistance containing As There is the As of 0.025 mass % or more.On the other hand, even if containing the As for having more than 0.07 mass %, the effect of corrosion resistance raising Also it can be saturated, therefore the content of As is 0.07 mass % hereinafter, preferably 0.05 mass % or less.

Bi further increases the machinability of copper alloy.For this reason, it may be necessary to which the Bi containing 0.005 mass % or more, preferably contains There is 0.006 mass % or more.On the other hand, although Bi is still uncertain to the harmfulness of human body, from strong to impact characteristics, high temperature The influence of degree, hot-workability and cold-workability considers that the upper limit of the content of Bi is set as 0.10 mass % hereinafter, being preferably set to 0.05 Quality % or less.

The target of present embodiment is that have good ductility, cold-workability and toughness together with high intensity, Sb, As, Bi is the element for improving corrosion resistance etc., if containing excessive, the not only effect saturation of corrosion resistance, and ductility, it is cold plus Work and toughness are damaged instead.Therefore, the total content of Sb, As and Bi are preferably 0.10 mass % hereinafter, more preferably 0.09 Quality % or less.

(Sn, Al, Fe, Cr, Mn, Co and inevitable impurity)

As the inevitable impurity in present embodiment, for example, can enumerate Al, Ni, Mg, Se, Te, Fe, Mn, Sn, Co, Ca, Zr, Cr, Ti, In, W, Mo, B, Ag and rare earth element etc..

All the time, free-cutting machinability copper alloy is using the copper alloy recycled as main material, rather than excellent with cathode copper, electrolytic zinc etc. Based on matter raw material.In the subsequent processing (downstream process, manufacturing procedure) in the field, cutting is implemented to most of component, component Processing, relative material 100 generate largely discarded copper alloy with 40~80 ratio.Such as can enumerate chip, trimming, flash, It flows over road (runner) and comprising manufacturing upper undesirable product etc..These discarded copper alloys become main material.If cutting is cut Bits etc. separation it is insufficient, then from other free-cutting machinability copper alloys be mixed into Pb, Fe, Mn, Se, Te, Sn, P, Sb, As, Bi, Ca, Al, Zr, Ni and rare earth element.Also, contain in cutting from tool mixed Fe, W, Co, Mo etc..Since waste material contains The product of plating, therefore it is mixed into Ni, Cr, Sn.Mg, Fe, Cr, Ti, Co, In, Ni, Se, Te are mixed into fine copper system waste material.From resource Recycling in terms of and cost problem consider, at least not to characteristic generate adverse effect in the range of, contain these elements The waste materials such as chip be used as raw material within certain limits.

Rule of thumb, Ni is mixed into from waste material etc. mostly, and the amount of Ni is permitted to less than 0.06 mass %, preferably less than 0.05 mass %.

Fe, Mn, Co, Cr and Si form intermetallic compound, in some cases with p-shaped at intermetallic compound, thus Influence machinability, corrosion resistance and other characteristics.Although difference, Fe according to the content of Cu, Si, Sn, P, relational expression f1, f2 Easy and Si chemical combination, and the Si with Fe equivalent may be consumed containing Fe, and promote have dysgenic Fe-Si to machinability The formation of compound.Therefore, the respective amount of Fe, Mn, Co and Cr is preferably 0.05 mass % hereinafter, more preferably 0.04 mass % Below.In particular, being preferably set to the total of the content of Fe, Mn, Co and Cr less than 0.08 mass %.The total amount is more preferably 0.06 Quality % is hereinafter, further preferably 0.05 mass % or less.

On the other hand, from mixed Sn and Al such as other free-cutting machinability copper alloys, the wastes for implementing plating in this reality Apply the formation for promoting γ phase in the alloy of mode.In addition, in the phase boundray of the α phase and κ phase that primarily form position as γ phase, It may cause the concentration rising for not forming γ phase and Sn, Al.The increase of γ phase and Sn, Al are in α-κ phase boundray (α phase and κ phase Phase boundray) segregation ductility, cold-workability, impact characteristics and hot properties can be made to reduce, also, with ductility reduction, It may cause tensile strength decline, therefore the amount of Sn, Al as inevitable impurity must also be limited.Sn, Al are respective Content is preferably 0.05 mass % hereinafter, more preferably 0.03 mass % or less.Also, the total needs of the content of Sn, Al are set For 0.06 mass % hereinafter, more preferably 0.04 mass % or less.

Moreover, the total amount of Fe, Mn, Co, Cr, Sn and Al are preferably 0.10 mass % or less.

On the other hand, Cu is considered as Ag, general Ag, and various characteristics is had little effect, there is no need to special Limitation, but preferably less than 0.05 mass %.

Te, Se its element itself have free-cutting machinability, although rare may largely be mixed into.If it is considered that ductility With the influence of impact characteristics, the respective content of Te, Se is preferably less than 0.03 mass %, further preferably less than 0.02 matter Measure %.

The respective amount of Al, Mg, Ca, Zr, Ti, In, W, Mo, B and rare earth element as other elements is preferably less than 0.03 mass %, more preferably less than 0.02 mass %, further preferably less than 0.01 mass %.

In addition, the amount of rare earth element be Sc, Y, La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Tb and The total amount of one or more of Lu.

More than, it is excellent in order to which the processabilities such as ductility, impact characteristics, room temperature and elevated temperature strength, riveting are set as especially excellent Choosing management and the amount for limiting these inevitable impurity.

(component relationship formula f1)

Component relationship formula f1 is the formula for indicating the relationship between composition and metallographic structure, even if the amount of each element is above-mentioned In the range of regulation, if being unsatisfactory for component relationship formula f1, it is unable to satisfy the various characteristics that present embodiment is set as target. If component relationship formula f1 requires efforts in manufacturing process less than 78.0 anyway, ratio shared by γ phase also increases, Occurs β phase in some cases, also, the long side of γ phase is elongated, corrosion resistance, ductility, impact characteristics, hot properties are deteriorated. Therefore, the lower limit of component relationship formula f1 is 78.0 or more, preferably 78.2 or more, more preferably 78.5 or more, further preferably It is 78.8 or more.As component relationship formula f1 becomes preferred range, the area ratio of γ phase substantially reduces or becomes 0, extends Property, the intensity under cold-workability, impact characteristics, room temperature, hot properties and corrosion resistance improve.

On the other hand, the upper limit of component relationship formula f1 mainly influences ratio shared by κ phase, if component relationship formula f1 is greater than 80.8, then in the case where paying attention to ductility and impact characteristics, ratio shared by κ phase becomes excessive.Also, μ phase becomes easy It is precipitated.If κ phase and μ phase are excessive, ductility, impact characteristics, cold-workability, hot properties, hot-workability, corrosion resistance and cut Cutting property is deteriorated.Therefore, the upper limit of component relationship formula f1 is for 80.8 hereinafter, preferably 80.5 hereinafter, more preferably 80.2 or less.

In this way, by the way that within the above range, the copper alloy of excellent can be obtained in component relationship formula f1 regulation.In addition, As, Sb, Bi about alternatively element and the inevitable impurity that dictates otherwise, comprehensively consider their content, almost Component relationship formula f1 is not influenced, therefore is not prescribed by component relationship formula f1.

(component relationship formula f2)

Component relationship formula f2 is the formula for indicating composition and processability, various characteristics, relationship between metallographic structure.If group At relational expression f2 less than 60.2, then ratio shared by the γ phase in metallographic structure increases, other gold are easy to appear including β phase Symbolic animal of the birth year, and it is easy residual, so that corrosion resistance, ductility, impact characteristics, cold-workability, hot properties are deteriorated.Also, Crystal grain becomes thick when warm and hot forging, and is easy to produce rupture.Therefore, the lower limit of component relationship formula f2 is 60.2 or more, preferably 60.4 or more, more preferably 60.5 or more.

On the other hand, if component relationship formula f2 is more than 61.5, thermal change form drag increases, heat deformability decline, hot extrusion Material and warm and hot forging product may generate skin breakage out.Also, hold in the metallographic structure in the direction parallel with hot-working direction Easily occur that length is more than 1000 μm and width is more than α phase coarse as 200 μm.Coarse α phase if it exists, then machinability and Strength reduction is present in the length of α phase with the long side of the γ phase on the boundary of κ phase, although be unlikely to form γ phase, It is easy to produce the segregation of Sn and Al.Moreover, being difficult to 1 phase of κ occur in α phase, intensity is lower, machinability, high temperature if the value of f2 is high Characteristic and abrasion performance are deteriorated.Also, the range of setting temperature is that (liquidus temperature-solidus temperature) can be more than 50 DEG C, casting Shrinkage cavity (shrinkage cavities) when making becomes significant, is unable to get sound castings (sound casting).Therefore, The upper limit of component relationship formula f2 is 61.5 hereinafter, preferably 61.4 hereinafter, more preferably 61.3 hereinafter, further preferably 61.2 Below.If f1 is 60.2 or more and the upper limit of f2 is preferred value, the crystal grains fine of α phase becomes about 50 μm hereinafter, α phase becomes Uniform distribution.There is higher intensity, good ductility, cold-workability, impact characteristics, hot properties as a result, and become The alloy of balancing good between intensity and ductility, impact characteristics.

In this way, by being provided component relationship formula f2 in narrow range as described above, it can be with good yield The excellent copper alloy of manufacturing characteristics.In addition, about alternatively element As, Sb, Bi and dictate otherwise inevitable miscellaneous Matter comprehensively considers their content, has little influence on component relationship formula f2, therefore be not prescribed by component relationship formula f2.

(compared with patent document)

Herein, by the group of Cu-Zn-Si alloy documented in above patent document 3~12 and the alloy of present embodiment It is shown in table 1 at the result being compared.

In present embodiment and patent document 3, the content of the Sn of Pb and alternatively element is different.Present embodiment and specially In sharp document 4, the content of the Sn of Pb and alternatively element is different.In present embodiment and patent document 6,7, whether containing It is different in terms of Zr.It is different in terms of whether containing Fe in present embodiment and patent document 8.Present embodiment and patent document 9 In, it is different in terms of whether containing Pb and also different in terms of whether containing Fe, Ni, Mn.

As described above, the alloy of present embodiment in patent document 3~9 other than patent document 5 documented by In Cu-Zn-Si alloy, compositing range is different.In patent document 5, about facilitating intensity, machinability and abrasion performance and presence 1 phase of κ in α phase, f1, f2 are not recorded, and strength balance is relatively low.Patent document 11 is about being heated to 700 DEG C or more Soldering and about brazed structure.Patent document 12 is about rotary rolling mill to screw or the raw material of gear.

[table 1]

< metallographic structure >

There are 10 kinds or more of phases for Cu-Zn-Si alloy, complicated phase transformation can be generated, only by the relationship of compositing range, element Formula, not necessarily available target property.Eventually by the type of the specified and determining metal phase being present in metallographic structure And its range, target property can be obtained.

In the case where the Cu-Zn-Si alloy being made of multiple metal phases, the corrosion resistance of each phase is not identical and exists Superiority and inferiority.Corrode the phase that is mutually easiest to corrosion worst from corrosion resistance, or mutually adjacent from the phase of poor corrosion resistance and with this Phase between boundary start to be in progress.In the case where including the Cu-Zn-Si alloy of this 3 kinds of elements of Cu, Zn, Si, if such as will α phase, α ' phase, β (including β ') phase, κ phase, γ (including γ ') phase, the corrosion resistance of μ phase are compared, then the sequence of corrosion resistance α phase > α ' phase > κ phase > μ phase >=γ phase > β phase is followed successively by from excellent phase.The difference of corrosion resistance between κ phase and μ phase is especially Greatly.

Herein, the numerical value of the composition of each phase is changed according to the composition of alloy and the occupied area rate of each phase, it may be said that such as Under.

The Si concentration of each phase is followed successively by μ phase > γ phase > κ phase > α phase > α ' phase >=β phase from the sequence of concentration from high to low. Si concentration in μ phase, γ phase and κ phase is higher than the Si concentration of alloy.Also, the Si concentration of μ phase is about the 2.5 of the Si concentration of α phase ~about 3 times, the Si concentration of γ phase is about 2~about 2.5 times of the Si concentration of α phase.

The Cu concentration of each phase is followed successively by μ phase > κ phase >=α phase > α ' phase >=γ phase > β phase from the sequence of concentration from high to low. Cu concentration in μ phase is higher than the Cu concentration of alloy.

In Cu-Zn-Si alloy shown in patent document 3~6, the cutting optimal different γ phase of sexual function is mainly mutually total with α ' It deposits, or is present in the boundary between κ phase, α phase.γ phase is under severe water quality for copper alloy or under environment, The selectively erosion progress as the generating source (starting point of corrosion) of corrosion.Certainly, if there is β phase, then corrode in γ phase β phase starts to corrode before.When μ phase coexists with γ phase, the corrosion ratio γ phase of μ phase is slightly started simultaneously at late or almost.Such as work as α When phase, κ phase, γ phase, μ phase coexist, if γ phase and μ phase selectivity carry out Dezincification corrosion, the γ phase being corroded passes through with μ phase Dezincification phenomenon and become rich in Cu corrosion product, which corrode κ phase or adjacent α ' mutually, to corrode company Lock reactor it is in progress.Therefore, β phase is necessary for 0%, and γ phase, μ phase are preferably as few as possible, it is generally desirable to eliminate them.

In addition, the water quality of the drinking water including Japan all over the world is varied, and its water quality is increasingly becoming copper The water quality that alloy easily corrodes.Although such as with the upper limit, sterilisation purpose to be used for due to the safety issue to human body The concentration of residual chlorine increases, and the copper alloy as running water pipe utensil becomes the environment easily corroded.As also included the vapour Vehicle component, mechanical part, industrial piping component use environment it is such, about being mingled under the use environment of many solution Corrosion resistance, it may also be said to which identical as drinking water, the necessity for reducing the phase of corrosion-vulnerable is increasing.

Also, since γ phase is hard and crisp phase, to copper alloy component apply relatively large load when, it is microcosmic on become Stress raiser.γ phase is primarily present in elongated α-κ phase boundray (phase boundray of α phase and κ phase).And γ phase becomes stress collection Middle source, therefore as the starting point of chip segmentation and chip is promoted to divide in cutting, to have the effect of reducing cutting resistance. On the other hand, γ phase is due to becoming the stress raiser, so that ductility, cold-workability and impact characteristics is made to be deteriorated, with The shortage of ductility and tensile strength also reduces.Moreover, γ phase by α phase, κ phase boundary centered on and exist, therefore make high temperature Creep strength decline.The target of the alloy of present embodiment be high intensity, ductility, excellent impact characteristics, hot properties, because This has to limit the amount of γ phase and the length of long side.

μ phase is primarily present in the phase boundray of the grain boundary of α phase, α phase, κ phase, therefore identical as γ phase become microcosmic and answer Power concentrated source.Due to becoming stress raiser or Grain Boundary Sliding phenomenon, μ phase increases stress-corrosion cracking sensitivity, reduces impact Characteristic, and reduce the intensity of ductility, cold-workability and room temperature and high temperature.In addition, identically as γ phase, there is μ phase improvement to cut The effect of cutting property, but its effect is much smaller compared with γ phase, and therefore, it is necessary to limit the length of the amount of μ phase, long side.

However, if be significantly reduced or eliminated to improve the various characteristics γ phase or γ phase and μ phase there are ratio, Then only by the way that satisfactory machinability may be unable to get containing a small amount of Pb and α phase, α ' phase, κ phase this 3 phase.Therefore, it is On improve containing a small amount of Pb and premised on there is excellent machinability ductility, impact characteristics, intensity, elevated temperature strength and Corrosion resistance needs the composition phase (metal phase, crystalline phase) of following regulation metallographic structure.

In addition, hereinafter, the unit of ratio shared by each phase (there are ratios) is the area ratio (area %).

(γ phase)

γ phase is the phase most helpful in the machinability of Cu-Zn-Si alloy, but in order to make corrosion resistance under adverse circumstances, Intensity, hot properties, ductility, cold-workability, impact characteristics under room temperature become excellent, it has to limit γ phase.In order to same When meet machinability and various characteristics, define component relationship formula f1, f2, aftermentioned membership credentials formula and manufacturing process.

(β phase and other phases)

In order to obtain high ductibility, impact characteristics, intensity, elevated temperature strength, metallographic by obtaining good corrosion resistance The ratio of β phase, γ phase, μ phase and other equal phases of ζ shared by tissue is particularly important.

Ratio regular meeting shared by β phase generates adverse effect to various characteristics, therefore at least can not be aobvious with the metal of 500 times of multiplying powers Micro mirror is observed, that is, needs the ratio being set as 0%.

Ratio, preferably 0.3% shared by other equal phases of ζ in addition to α phase, κ phase, β phase, γ phase, μ phase are hereinafter, more Preferably 0.1% or less.Other equal phases of ζ are most preferably not present.

Firstly, excellent corrosion resistance, intensity, ductility, cold-workability, impact characteristics and hot properties in order to obtain, Need for ratio shared by γ phase to be set as 0.3% hereinafter, and the length of the long side of γ phase is set as 25 μm or less.In order into one Step improves these characteristics, ratio shared by γ phase be preferably 0.1% hereinafter, can not with 500 times of micro- sem observation γ phase, also Being is most preferably 0% in the quality entity for say γ phase.

The length of the long side of γ phase measures by the following method.Such as with 500 times or 1000 times of metallic micrograph, The maximum length of the long side of γ phase is measured in 1 visual field.As be described hereinafter, the operation is carried out in any visual field in 5 visual fields. Calculate the average value of the maximum length of the long side of γ phase obtained in each visual field, and the length of the long side as γ phase.Therefore, The length of the long side of γ phase could also say that the maximum length of the long side of γ phase.

Even if ratio shared by γ phase is lower, in two dimension observation, γ phase is also centered on phase boundray and with elongated shape Shape exists.If the length of the long side of γ phase is longer, the corrosion on depth direction accelerates and encourages high-temerature creep, to make Ductility, tensile strength, impact characteristics and cold-workability reduce.

The length of the long side of γ phase needs to be set as 25 μm hereinafter, being preferably set to 15 μm or less as a result,.In addition, 500 can be used Times microscope be clearly determined as γ phase size be long side length be about 3 μm or more γ phase.It is small with regard to the length of long side For about 3 μm of γ phase, if its amount is few, tensile strength, ductility, hot properties, impact characteristics, cold is had little influence on Processability and corrosion resistance, therefore the γ phase can be ignored.About machinability, the copper that the presence of γ phase improves present embodiment is closed The effect of the machinability of gold is maximum, but the various problems possessed by the γ phase consider, need to eliminate as much as γ phase, aftermentioned κ 1 Mutually become the substitution of γ phase.

The length of the long side of ratio shared by γ phase and γ phase has with the content of Cu, Sn, Si and component relationship formula f1, f2 Very big correlation.

(μ phase)

Since although μ phase has the effect of improving machinability, from influence corrosion resistance and ductility, cold-workability, From the aspect of impact characteristics, room temperature tensile strength, hot properties, at least need for ratio shared by μ phase to be set as 0% or more and 1.0% or less.Ratio shared by μ phase is preferably 0.5% hereinafter, more preferably 0.3% hereinafter, being most preferably there is no μ phase.μ Mutually it is primarily present in grain boundary, phase boundray.Therefore, in the presence of a harsh environment, μ phase grain boundary present in μ phase generates brilliant Boundary's corrosion.The μ phase for being slenderly present in crystal boundary makes the impact characteristics and ductility reduction of alloy, and due to the drop of ductility Low, as a result tensile strength also reduces.In addition, for example the valve of the engine rotation for automobile or in High-pressure air valve use copper When alloy, if being kept for a long time at a high temperature of 150 DEG C, crystal boundary is easy to produce sliding, creep.Therefore, it is necessary to limit μ The amount of phase, while the length of the long side for the μ phase for being primarily present in grain boundary is set as 20 μm or less.The length of the long side of μ phase Preferably 15 μm hereinafter, more preferably 5 μm or less.

The length of the long side of μ phase can be measured by the identical method of measuring method of the length of the long side with γ phase.That is, According to the size of μ phase, on the basis of 500 times, 1000 times of metallic micrograph or the two of 2000 times or 5000 times are used sometimes Secondary charge pattern photo (electron micrograph) measures the maximum length of the long side of μ phase in 1 visual field.Appointing in 5 visual fields The operation is carried out in meaning visual field.The average value of the maximum length of the long side of μ phase obtained in each visual field is calculated, and as μ phase Long side length.Therefore, the length of the long side of μ phase could also say that the maximum length of the long side of μ phase.

(κ phase)

Under the conditions of high-speed cutting in recent years, the cutting ability of the material including cutting resistance, chip discharge It is most important.But in order to which ratio shared by the γ phase with most excellent cutting sexual function is being limited to 0.3% shape below Has excellent machinability under state, ratio shared by κ phase at least needs to be set as 29% or more.Ratio shared by κ phase is preferably 33% or more, more preferably 35% or more.It is 38% or more if paying attention to intensity.

Compared with γ phase, μ phase, β phase, κ phase is not crisp, and more rich in ductility, excellent corrosion resistance.γ phase, μ phase along The crystal boundary and phase boundray of α phase and exist, but κ Xiang Zhongwei observes this tendency.It is intensity, machinability, wear-resisting also, by α phase Consumption and hot properties are excellent.

Ratio shared by κ phase increases, and machinability improves, and tensile strength, elevated temperature strength are high, and abrasion performance is got higher.But It is that on the other hand, with the increase of κ phase, ductility, cold-workability and impact characteristics are gradually decreased.Moreover, if shared by κ phase Ratio reaches about 50%, then the effect that machinability improves also is saturated, and if κ phase increase, cut since κ phase is hard and intensity height Cut resistance increase.Also, if the amount of κ phase is excessive, and chip tends to be continuous.Moreover, if ratio shared by κ phase reaches about 60%, The then tensile strength saturation with the reduction of ductility, cold-workability and hot-workability are also deteriorated.If comprehensive descision is strong in this way Degree, ductility, impact characteristics and machinability then need ratio shared by κ phase being set as 60% or less.κ phase be preferably 58% with It is lower or 56% hereinafter, more preferably 54% hereinafter, in particular, if pay attention to ductility, impact characteristics, riveting or bendability, It is then 50% or less.

κ phase has excellent cutting sexual function with γ phase together, since γ phase is primarily present in phase boundray, and in cutting As stress raiser, thus, it is possible to obtain excellent chip segmentation property with a small amount of γ phase, to reduce cutting resistance.Rear It states in the relational expression f6 of machinability, the coefficient of the amount of 6 times of κ phases is imparted to the square root of the amount of γ phase.On the other hand, κ phase It will not be tended to as γ phase, μ phase and be formed together metallographic structure with α phase in phase boundray, and sent out and being coexisted with soft α phase Wave the function of improving machinability.In other words, κ phase with soft α phase by coexisting, to play the machinability for improving κ phase Function, and the function is accordingly played with the admixture of the amount of κ phase or α phase and κ phase.Therefore, the distribution shape of α phase and κ phase State also influences machinability, if forming coarse α phase, machinability is deteriorated.When substantially limiting ratio shared by γ phase, κ phase The effect saturation that amount nearby makes the effect for improving chip segmentation property for boundary and reduce cutting resistance with about 50%, and then with κ The increase of the amount of phase and be gradually deteriorated.That is, even if κ phase becomes excessively, also to become with the component ratio and admixture of soft α phase Difference, so that the segmentation of chip gradually decreases.Moreover, the influence of the high κ phase of intensity becomes if the ratio of κ phase is more than about 50% By force, cutting resistance becomes larger.

In order in a small amount of Pb and the area ratio of the excellent γ phase of cutting ability is limited in 0.3% or less, preferably Excellent machinability is obtained in the state of being limited in 0.1% or 0%, not only needs to improve the amount of κ phase, it is also necessary to improve α phase Machinability.That is, the machinability of α phase improves by making in α phase there are 1 phase of needle-shaped κ phase or κ, thus hardly damage ductility and Improve the cutting ability of alloy.And the increase of the amount with 1 phase of κ being present in α phase, the machinability of alloy further mention It is high.Wherein, although according to relational expression and manufacturing process difference, the κ 1 with the increase of the κ phase in metallographic structure, in α phase The amount of phase also increases.Meeting there are excessive κ 1 makes the ductility reduction of α phase itself, and to the ductility of alloy, cold-workability And impact characteristics generate adverse effect, it is therefore desirable to which ratio shared by κ phase is set as 60% hereinafter, κ phase is preferably 58% or less Or 56% or less.In the above manner, the ratio as κ phase shared in metallographic structure, has from good balance and all prolongs The sight of balance between malleability, cold-workability, intensity, impact characteristics, corrosion resistance, hot properties, machinability and abrasion performance Point consideration, most preferably about 33%~about 56%.Although also, it is different according to the value of f1, f2, but if ratio shared by κ phase Example is 33% or more and 56% hereinafter, then the amount of 1 phase of κ in α phase also increases, though the content of Pb less than 0.020 mass %, It can ensure good machinability.

(presence of the elongated needle-shaped κ phase (1 phase of κ) in α phase)

If meet above-mentioned composition, component relationship formula f1, f2, process important document, needle-shaped κ phase will be present in α phase.The κ phase It is harder than α phase.Be present in the κ phase (1 phase of κ) in α phase with a thickness of about 0.1 μm to about 0.2 μm or so (about 0.05 μm~about 0.5 μ M), the feature of thickness is thin, elongated and to be needle-shaped.By making that following effect can be obtained there are needle-shaped 1 phase of κ in α phase.

1) α phase enhances, and the tensile strength as alloy improves.

2) machinability of α phase improves, and the machinabilities such as cutting resistance decline or chip segmentation property raising of alloy improve.

3) due to being present in α phase, adverse effect is not generated to the corrosion resistance of alloy.

4) α phase enhances, and the abrasion performance of alloy improves.

5) due to being present in α phase, the influence to ductility, impact characteristics is very slight.

The needle-shaped κ phase being present in α phase influences the constitution elements such as Cu, Zn, Si and relational expression f1, f2 and manufacturing process. When the important document of the composition and metallographic structure that meet present embodiment, Si is one of the existing principal element for influencing 1 phase of κ, is made As an example of, if Si amount is about 2.95 mass % or more, come into existence 1 phase of κ in α phase.If Si amount is about 3.05 mass % or more, Then 1 phase of κ becomes obviously, if about 3.15 mass % or more, 1 phase of κ exist in which will be apparent from.Also, the presence of 1 phase of κ by The influence of relational expression, such as when component relationship formula f2 needs for 61.5 hereinafter, will be present as f2 becomes 61.2,61.0, κ, 1 phase More.

On the other hand, though crystal grain size be 2~100 μm α crystal grain or the width of 1 phase of κ in α phase be only about 0.2 μ M can also damage ductility possessed by α phase and impact is special if ratio shared by 1 phase of κ increases, i.e. the amount of 1 phase of κ becomes excessively Property.The amount of 1 phase of κ in α phase is mainly related with the amount of the κ phase in metallographic structure, and content, relational expression by Cu, Si, Zn The very big influence of f1, f2 and manufacturing process.If being more than 60% as ratio shared by the κ phase in the metallographic structure of principal element, The amount for 1 phase of κ being then present in α phase becomes excessive.From the viewpoint of 1 phase of κ for the appropriate amount being present in α phase, metallographic group The amount of κ phase in knitting is for 60% hereinafter, preferably 58% hereinafter, more preferably 54% payes attention to ductility, cold-workability hereinafter, working as And when impact characteristics, preferably 54% hereinafter, further preferably 50% or less.Also, the ratio shared by the κ phase is high and f2 It is worth hour, the amount of 1 phase of κ increases.On the contrary, being present in the amount of 1 phase of κ in α phase when the ratio shared by the κ phase is low and the value of f2 is big It reduces.

It is present in for 1 phase of κ in α phase, if being put using metallurgical microscopes with 500 times of multiplying power, in some cases It is big to arrive about 1000 times, then it is able to confirm that as thin thread, spicule.But the area ratio due to being difficult to calculate 1 phase of κ, 1 phase of κ in α phase is set as being contained in the area ratio of α phase.

(membership credentials formula f3, f4, f5)

Excellent corrosion resistance, ductility, impact characteristics and elevated temperature strength in order to obtain need ratio shared by α phase, κ phase The total (membership credentials formula f3=(α)+(κ)) of example is 98.6% or more.The value of f3 is preferably 99.3% or more, more preferably 99.5% or more.In the same manner, α phase, κ phase, γ phase, the total of ratio shared by μ phase (membership credentials f4=(α)+(κ)+(γ)+ (μ)) it is 99.7% or more, preferably 99.8% or more.

In addition, the ratio (f5=(γ)+(μ)) of total shared by γ phase, μ phase is 0% or more and 1.2% or less.F5's Value preferably 0.5% or less.

Herein, in relational expression f3~f6 of metallographic structure, with α phase, β phase, γ phase, δ phase, ε phase, ζ phase, η phase, κ phase, μ This 10 kinds of metal phases of phase, χ phase are object, and intermetallic compound, oxide, non-metallic inclusion, does not melt substance etc. at Pb particle Not as object.Also, the needle-shaped κ phase (1 phase of κ) for being present in α phase is included in α phase, and can not use 500 times or 1000 times of gold Belong to the μ phase of micro- sem observation by except.In addition, passing through Si, P and inevitably mixed element (such as Fe, Co, Mn) formation Intermetallic compound outside the scope of application of metal phase the area ratio.But these intermetallic compounds influence machinability, therefore Need to pay close attention to inevitable impurity.

(membership credentials formula f6)

In the alloy of present embodiment, although the content of Pb is maintained at minimum limit in Cu-Zn-Si alloy, cutting Property is also good, and needs to meet all impact characteristics, ductility, cold-workability, voltage endurance, room temperature and elevated temperature strength and resistance to Corrosivity.However, machinability and impact characteristics, ductility, corrosion resistance are contradictory characteristics.

From the aspect of metallographic structure, comprising the γ phase that more cutting abilities is most excellent, machinability is better, but from impact From the aspect of characteristic, ductility, intensity, corrosion resistance and other characteristics, it has to reduce γ phase.It knows and works as shared by γ phase When ratio is 0.3% or less, good machinability in order to obtain is needed the value of above-mentioned membership credentials formula f6 according to experimental result It is located in appropriate range.

Since the cutting ability of γ phase is most excellent, in membership credentials formula f6 relevant to cutting ability, to γ phase The subduplicate value of shared ratio ((γ) (%)) assigns high 6 times of coefficient.On the other hand, the coefficient of κ phase is 1.κ phase and α It is mutually formed together metallographic structure, and does not tend in γ phase, this phase boundray of μ phase and plays effect according to there are ratio.For Good cutting ability is obtained, needing membership credentials formula f6 is 30 or more.F6 is preferably 33 or more, and more preferably 35 or more.

On the other hand, if membership credentials formula f6 is more than 62, machinability is deteriorated instead, and impact characteristics, ductility are bright It is aobvious to be deteriorated.It is 62 or less therefore, it is necessary to membership credentials formula f6.The value of f6 is preferably 58 hereinafter, more preferably 54 or less.

< characteristic >

(normal temperature strength and elevated temperature strength)

As the containers related to hydrogen or in high pressure hydrogen environment such as the valve of drinking water, utensil, hydrogen station, hydrogen power generation, Connector, piping, valve, intensity needed for the various fields including the valve of automobile, connector, tensile strength are taken seriously.And And such as the valve that uses or high temp/high pressure valve are exposed to a maximum of about of 150 DEG C of temperature in the environment of close to the engine room of automobile It spends under environment, requires will not to deform when being applied with pressure, stress at this time or brisement.In the case where pressure vessel, allow Stress influence tensile strength.Pressure vessel requires required minimal ductility and impact with use condition depending on the application Characteristic, and suitably the balance by it between intensity and determine.Also, strong request becomes this reality including automobile component Apply mode using the component of object, being thinning of component, lightweight.

For this purpose, the hot extrusion material, hot calender material and hot forged material as hot-working material are preferably anti-under room temperature Tensile strength is 550N/mm²Above high-strength material.Tensile strength under room temperature is more preferably 580N/mm²More than, it is further excellent It is selected as 600N/mm²More than, most preferably 625N/mm²More than.Major part in valve and pressure vessel is made by warm and hot forging, As long as can have 580N/mm²It above, is preferably 600N/mm²Above tensile strength, then not due to the alloy of present embodiment It can cause hydrogen embrittlement and can substitute such as becoming the hydrogen valve of problem, hydrogen power generation valve in terms of black brittleness, to produce Utility value in industry improves.In addition, hot forged material is not implemented generally to be cold worked.Although such as surface can be made by shot-peening Hardening, but it is essentially only 0.1~1.5% or so cold working rate, tensile strength rises to 2~15N/mm²Left and right.

The alloy of present embodiment under the conditions of the high temperature appropriate of the recrystallization temperature than material by implementing at heat It manages or implements thermal history appropriate and improve tensile strength.Specifically, compared with the hot-working material before heat treatment, although root It is different according to composition and heat treatment condition, but tensile strength improves about 10~about 100N/mm².In addition to Corson alloy or Ti-Cu this Other than kind age-hardening type alloy, in copper alloy almost without discovery and the high heat treatment of the temperature than recrystallization temperature The example that tensile strength rises.Think that the reasons why improving intensity by the alloy of present embodiment is as follows.By at 505 DEG C or more and 575 DEG C it is below it is appropriate under the conditions of be heat-treated, the α phase in base softens with κ phase.On the other hand, following situation is significantly super Cross the softening of α phase, κ phase, that is, the case where α phase enhances and making in α phase there are needle-shaped κ phase；By reducing γ phase ductility The case where increasing and being resistant to the peak load increase of brisement；And κ phase ratio increase the case where.By these situations, with Hot-working material is compared, and not only corrosion resistance greatly improves, but also tensile strength, ductility, impact value, cold-workability are substantially It improves, high-intensitive and high ductibility, high tenacity alloy is made.

On the other hand, in some cases, hot-working material is after heat treatment appropriate by cold stretch, bracing wire, calendering And improve intensity.In the alloy of present embodiment, when in the case where implementing cold working, cold working rate is 15% or less, often 1% cold working rate, tensile strength rise about 12N/mm².In contrast, every 1% cold working rate, impact characteristics reduce about 4%.Or Person, if the impact value of heat treatment material is set as I₀, cold working rate is set as to RE%, then be cold worked after impact value I_RCold It is I that working modulus can substantially arrange under the conditions of being 20% below_R=I₀×(20/(20+RE)).For example, when being to tensile strength 580N/mm², impact value 30J/cm²Alloy material implement cold working rate 5% cold stretch come make cold working material when, it is cold The tensile strength of rapidoprint is about 640N/mm², impact value is as about 24J/cm².If cold working rate is different, tensile strength, Impact value cannot be uniquely determined.

In this way, tensile strength is got higher if implementing cold working, but impact value, elongation reduce.In order to obtain depending on the application To as the intensity of target, elongation, impact value, need to set cold working rate appropriate.

On the other hand, if being stretched, bracing wire, the cold working such as calendering, then implement the heat treatment of felicity condition, then with heat Rapidoprint, especially compared with hot extrusion material, tensile strength, elongation, impact characteristics improve.In addition, can not use sometimes Forged article etc. implements tension test.In this case, Rockwell B grade (HRB) and tensile strength (S) have stronger correlativity, because This can be simply measured with Rockwell B grade and speculate tensile strength.Wherein, the correlativity is to meet present embodiment Composition, and premised on meeting the important document of f1~f6.

When HRB is 65 or more and 88 or less: S=4.3 × HRB+242

When HRB is more than 88 and is 99 or less: S=11.8 × HRB-422

Tensile strength when HRB is 65,75,85,88,93,98 is substantially estimated as 520 respectively, 565,610,625,675, 735N/mm²。

About hot properties, in the state that load has the stress for 0.2% yield strength for being equivalent to room temperature, at 150 DEG C The lower creep strain by after copper alloy holding 100 hours is preferably 0.3% or less.The creep strain be more preferably 0.2% hereinafter, Further preferably 0.15% or less.In this case, even if the valve material of the engine room of such as high temperature high pressure valve, close automobile It is exposed under high temperature, is also unlikely to deform, having excellent high-temperature strength like that.

Even and if tensile strength good in machinability is high also to lack ductility, in the case where cold-workability, purposes by Limitation.About cold-workability, such as the purposes of running water pipe correlation utensil, tube parts, automobile, electric component, sometimes Implement the cold working such as slight riveting processing or bending to hot forged material, machining material, and they must will not be ruptured. Machinability is to divide chip and a kind of brittleness but characteristic contradictory with cold-workability to material requirements.In the same manner, tension Intensity and ductility are contradictory characteristics, and high balance is preferably obtained in tensile strength and ductility (elongation).That is, at least Tensile strength is 550N/mm²More than, elongation be 12% or more, and tensile strength (S) with (elongation (E%)+100)/ 100 } the product f8=S of 1/2 power × { (E+100)/100 }^1/2Value be preferably 675 or more this become high intensity/high ductibility One scale of material.F8 is more preferably 690, further preferably 700 or more.When include with 2~15% cold working rate into When capable cold working, 12% or more elongation and 630N/mm can be had both²It above, is further 650N/mm²Above is anti- Tensile strength, f8 reach 690 or more, further reach 700 or more.

In addition, crystal grain is easy to become thick for casting, it sometimes also include microdefect, therefore be set to be applicable in outer Product.

It include Zn and inevitable impurity containing Pb in the Cu containing 60 mass %, the Pb of 3 mass % and remainder Free-cutting brass in the case where, hot extrusion material, the tensile strength of warm and hot forging product at normal temperature be 360N/mm²~400N/ mm², elongation is 35%~45%.That is, f8 is about 450.Also, even if having 0.2% surrender for being equivalent to room temperature strong in load In the state of the stress of degree, after exposing alloy to the open air 100 hours at 150 DEG C, creep strain is also about 4~5%.Therefore, with The existing free-cutting brass containing Pb is compared, and tensile strength, the heat resistance of the alloy of present embodiment are high levels.That is, The excellent corrosion resistance of the alloy of present embodiment, and have high intensity at room temperature, when long even if adding the high intensity Between be exposed under high temperature and also hardly deform, therefore thin-walled, light weight can be realized using high intensity.Especially high pressure gas, It can not substantially implement to be cold worked in the case where the forged materials such as High Pressure Hydrogen valve, therefore can be allowed using high intensity to increase Pressure or realization be thinning, lightweight.

Also, the cold-workabilities such as the riveting processing of the free-cutting machinability copper alloy containing 3% Pb are poor.

The hot properties of the alloy of present embodiment is also roughly the same for extruded material, the material for implementing cold working. That is, 0.2% yield strength improves, even if being equivalent to raising being applied with by the cold working by implementing cold working In the state of the load of 0.2% yield strength, the creep strain after alloy is exposed to the open air 100 hours at 150 DEG C is also 0.3% Below and has high-fire resistance.Hot properties mainly influences the area ratio of β phase, γ phase, μ phase, their the area ratio is higher, the height Temperature characteristics become poorer.Also, the length for being present in the grain boundary of α phase and the μ phase of phase boundray, the long side of γ phase is longer, high Temperature characteristics become poorer.

(impact resistance)

In general, becoming fragile when material has high-intensitive.In cutting, the excellent material of the segmentation of chip is considered to have Certain brittleness.Impact characteristics and machinability, impact characteristics and intensity are contradictory characteristic in terms of certain.

However, when copper alloy is used in the drinking water such as valve, connector, valve utensil, automobile component, mechanical part, industrial matches When the various components such as pipe, copper alloy not only needs for high intensity, it is also necessary to impact-resistant characteristic.Specifically, being tried with U-shaped recess When piece carries out Charpy-type test, Charpy-type test value (I) is preferably 12J/cm²More than.When including cold working, with it Working modulus increases and impact value reduces, but more preferably 15J/cm²More than.On the other hand, the hot-working material of cold working is not carried out In material, Charpy-type test value is preferably 15J/cm²More than, more preferably 16J/cm²More than, further preferably 20J/cm²With On, most preferably 24J/cm²More than.The alloy of present embodiment is the alloy about excellent in machinability, and is not needed especially Wanting Charpy-type test value is more than 50J/cm².If Charpy-type test value is more than 50J/cm², then ductility and toughness increases instead Add, therefore cutting resistance increases, chip becomes easy continuously, and machinability is deteriorated.Therefore, Charpy-type test value is preferably 50J/ cm²Below.

If the κ phase for facilitating the hard of the intensity of material, machinability is excessively increased or the amount of 1 phase of κ is excessively increased, tough Property, that is, impact characteristics reduction.Therefore, intensity and machinability and impact characteristics (toughness) are contradictory characteristic.It is defined on by following formula Intensity/elongation/impact equilibrium index f9 of impact characteristics is increased on intensity/elongation.

About hot-working material, if tensile strength (S) is 550N/mm²More than, elongation (E) is 12% or more, Charpy Impact test value (I) is 12J/cm²More than, and the product of 1/2 power of S and { (E+100)/100 }, with I's and f9=S × {(E+100)/100}^1/2+ I is preferably 700 or more, and more preferably 715, further preferably 725 or more, then it can be described as high intensity And has the material of high elongation rate and toughness.When including the cold working carried out with 2~15% working modulus, further preferred f9 It is 740 or more.

Preferably satisfying the intensity/ductility balanced index f8 is 675 or more or intensity/ductility/impact equilibrium index F9 is 700 any of the above persons.Impact characteristics and elongation both of which are the scale of ductility, and more preferably they are divided For static ductility and instantaneous ductility, meet both f8, f9.

Impact characteristics and metallographic structure have close relationship, and γ phase, μ phase make impact characteristics be deteriorated.If also, γ phase, μ phase It is present in the grain boundary of α phase, the phase boundray of α phase, κ phase, then grain boundary and phase boundray become fragile and impact characteristics are deteriorated.As above It is described, it is not only the area ratio, and the length of γ phase, the long side of μ phase also has an impact impact characteristics.

< manufacturing process >

Then, the manufacturing method of the of the invention the 1st, the high-strength simple-cutting copper alloy of 2 embodiments is illustrated.

The metallographic structure of the alloy of present embodiment not only changes in the composition, but also also occurs in manufacturing process Variation.Not only influenced by hot extrusion, the hot processing temperature of warm and hot forging, heat treatment condition, but also hot-working or heat treatment Average cooling rate (being also referred to as cooling velocity) in cooling procedure also brings along influence.The result furtherd investigate obtains Know, it is cold under the temperature region of 450 DEG C to 400 DEG C of metallographic structure larger impact in the cooling procedure of hot-working and heat treatment But the cooling velocity under speed and 575 DEG C to 525 DEG C of temperature region.

The manufacturing process of present embodiment is necessary process for the alloy of present embodiment, although also to take into account Composition, but substantially play following important conduct.

1) the γ phase for making ductility, intensity, impact characteristics and corrosion resistance be deteriorated is significantly reduced or eliminated, and reduces γ phase Long side length.

2) inhibit the generation for the μ phase for making ductility, intensity, impact characteristics and corrosion resistance be deteriorated, and control the long side of μ phase Length.

3) needle-shaped κ phase is appeared in α phase.

(melting casting)

It is dissolved in about 100 DEG C higher than the fusing point (liquidus temperature) of the alloy of present embodiment~about 300 DEG C of temperature i.e. It is carried out at about 950 DEG C~about 1200 DEG C.Casting and cast product are in about 50 DEG C~about 200 DEG C of temperature higher than fusing point i.e. about 900 DEG C~about 1100 DEG C at pour cast from as defined in mold, and it is cold by several cooling means progress such as air cooling, slow cooling, water cooling But.Moreover, various change mutually occurs for composition after solidification.

(hot-working)

As hot-working, hot extrusion, warm and hot forging, hot calender can be enumerated.

Material such as about hot extrusion, although different according to capacity of equipment, preferably when actually carrying out hot-working Temperature, specifically the rigid temperature (hot processing temperature) by after extrusion die implements hot extrusion under conditions of being 600~740 DEG C. If more than 740 DEG C at a temperature of carry out hot-working, many β phases are formed in plastic processing, β meets residual sometimes, γ phase Also there is more residual, to mutually generate adverse effect to composition after cooling.Also, even if implementing at heat in subsequent processing Reason, the metallographic structure of hot-working material also bring along influence.Hot processing temperature be preferably 670 DEG C hereinafter, more preferably 645 DEG C with Under.If in 645 DEG C or less implementation hot extrusions, the γ phase of hot extrusion material is reduced.In addition, α phase becomes particulate form, and intensity It improves.When heat treatment material after the hot extrusion material few using the γ phase produces hot forged material and warm and hot forging, heat The amount of γ phase becomes less in forging material, heat treatment material.

Moreover, can also obtain having machinability, corrosion resistance etc. by requiring efforts to the cooling velocity after hot extrusion The material of various characteristics.That is, in cooling procedure after hot extrusion, if under 575 DEG C to 525 DEG C of temperature region with 0.1 DEG C/ Minute or more and 3 DEG C/min of cooling velocities below cooled down, then γ phase is reduced.If cooling velocity is more than 3 DEG C/min, The reduction of the amount of γ phase can be insufficient.Cooling velocity under 575 DEG C to 525 DEG C of temperature region be preferably 1.5 DEG C/min with Under, more preferably 1 DEG C/min or less.Then, the cooling velocity under 450 DEG C to 400 DEG C of temperature region is set as 3 DEG C/min Above and 500 DEG C/min or less.Cooling velocity under 450 DEG C to 400 DEG C of temperature region is preferably 4 DEG C/min or more, more Preferably 8 DEG C/min or more.Thus the increase of μ phase is prevented.

In addition, not needing to control 575 DEG C after hot-working when being heat-treated in subsequent processing or final process The cooling velocity under cooling velocity, 450 DEG C to 400 DEG C of temperature region under to 525 DEG C of temperature regions.

Also, when hot processing temperature is lower, thermal change form drag increases.From the viewpoint of deformation energy, hot processing temperature Lower limit be preferably 600 DEG C or more.It, can be 600 when extrusion ratio is 50 or less or when hot forging causes fairly simple shape DEG C or more implement hot-working.If considering nargin, the lower limit of hot processing temperature is preferably 605 DEG C.Although according to capacity of equipment without Together, but preferably hot processing temperature is as low as possible.

Consider that can be surveyed locates, hot processing temperature is defined as after hot extrusion, warm and hot forging, hot calender after about 3 seconds or 4 The temperature of the hot-working material surveyed after second.Metallographic structure is influenced by just by the temperature after the processing of large plastometric set.

In present embodiment, in the cooling procedure after thermoplasticity processing, by 575 DEG C to 525 DEG C of temperature region with 0.1 DEG C/min or more and 3 DEG C/min of average cooling rates below cooled down.Then, by 450 DEG C to 400 DEG C of temperature region With 3 DEG C/min or more and 500 DEG C/min of average cooling rates below are cooled down.

The brass alloys of the Pb of amount containing 1~4 mass % account for the overwhelming majority of copper alloy extruded material, close in the brass In the case where gold, in addition to squeeze out diameter it is big, other than for example diameter is more than about 38mm, line is usually wound into after hot extrusion Circle.The ingot casting (small base) of extrusion is extruded device and seizes heat to which temperature reduces.Extruded material with winding device by contacting And it is taken away heat, so that temperature further decreases.From the ingot casting temperature initially squeezed out, or from the temperature of extruded material, with than About 50 DEG C~100 DEG C of temperature decline occurs for faster cooling velocity.Later, coiled coil is by heat insulation effect, although root Weight according to coil etc. and it is different, but with about 2 DEG C/min of slow cooling velocity by 450 DEG C to 400 DEG C of temperature region It is cooled down.When material temperature reaches about 300 DEG C, after average cooling rate it is further slack-off, therefore nationwide examination for graduation qualification sometimes Consider processing and carries out water cooling.In the case where the brass alloys containing Pb, with about 600~700 DEG C of progress hot extrusions, but just squeeze There is the largely β phase rich in hot-workability in metallographic structure after out.If the cooling velocity after squeezing out is fast, gold after cooling A large amount of β phase is remained in phase constitution, so that corrosion resistance, ductility, impact characteristics, hot properties are deteriorated.In order to avoid this Situation is cooled down so that the slow cooling velocity of heat insulation effect for squeezing out coil etc. is utilized, β phase is thus made to become α phase, To become the metallographic structure rich in α phase.As described, the cooling velocity of extruded material passes through and subtracts than very fast after freshly extruded Cooling after slow and become the metallographic structure rich in α phase.Although in addition, not about average cooling rate in patent document 1 Record, but disclose and slow cooling carried out with the purpose that reduces β phase and isolate β phase, until the temperature of extruded material becomes 180 DEG C or less.

In the above manner, the alloy of present embodiment is with the manufacturing method with the existing brass alloys containing Pb in heat Entirely different cooling velocity is manufactured in cooling procedure after processing.

(warm and hot forging)

Raw material as warm and hot forging mainly use hot extrusion material, but continuously casting stick also can be used.With hot extrusion It compares, complicated shape is processed into warm and hot forging, therefore the temperature of the raw material before forging is higher.But become forged article The temperature of the hot forged material for being applied with big plastic processing of main portions is i.e. from after just forging after about 3 seconds or the material temperature after 4 seconds Degree 600 DEG C to 740 DEG C of ground preferably identical as hot extrusion material.

As long as in addition, reducing extruding temperature when manufacturing hot extrusion pressure bar, and being set as the few metallographic structure of γ phase, then to this It is also available to maintain the hot forging tissue of the few state of γ phase even if hot forging temperature is high when hot extrusion pressure bar implements warm and hot forging.

In addition, can obtain having corrosion resistance, machinability etc. respectively by requiring efforts in cooling velocity after forging The material of kind characteristic.That is, the temperature after warm and hot forging by 3 seconds or the forged material of 4 seconds time points is 600 DEG C or more and 740 DEG C or less.In cooling procedure later, if in 575 DEG C to 525 DEG C of temperature region, especially in 570 DEG C to 530 DEG C of temperature In region, if γ phase is reduced with 0.1 DEG C/min or more and 3 DEG C/min of cooling velocities below are cooled down.From economy Considering, the lower limit value of the cooling velocity under 575 DEG C to 525 DEG C of temperature region is set as 0.1 DEG C/min or more, on the other hand, if Cooling velocity is more than 3 DEG C/min, then the reduction of the amount of γ phase becomes inadequate.Preferably 1.5 DEG C/min hereinafter, more preferably 1 DEG C/min or less.Moreover, the cooling velocity under 450 DEG C to 400 DEG C of temperature region is set as 3 DEG C/min or more and 500 DEG C/min or less.Cooling velocity under 450 DEG C to 400 DEG C of temperature region is preferably 4 DEG C/min or more, more preferably 8 DEG C/ Minute or more.Prevent μ phase from increasing as a result,.In this way, in 575~525 DEG C of temperature region, with 3 DEG C/min hereinafter, preferably 1.5 DEG C/min of cooling velocities below are cooled down.Also, in 450 to 400 DEG C of temperature region, with 3 DEG C/min with Upper, preferably 4 DEG C/min or more cooling velocities are cooled down.In this way, slowing down cooling in 575~525 DEG C of temperature region Speed, accelerates cooling velocity on the contrary in 450 to 400 DEG C of temperature region, and more suitable material is thus made.Hot extrusion material Material is the plastic processing on a direction, and forged article is generally complicated plastic deformation, therefore the reduction degree of γ phase, the length of γ phase The reduction degree of edge lengths is greater than hot extrusion material.

(hot calender)

It carries out repeating calendering, final hot calender temperature (material temperature after 3~4 seconds) in the case where hot calender Preferably 600 DEG C or more and 740 DEG C hereinafter, more preferably 605 DEG C or more and 670 DEG C or less.The cooling and heat of hot calender material It squeezes in the same manner, with 0.1 DEG C/min or more and 3 DEG C/min of cooling velocities below under 575 DEG C to 525 DEG C of temperature region It is cooled down, then, the cooling velocity under 450 DEG C to 400 DEG C of temperature region is set as 3 DEG C/min or more and 500 DEG C/minute Below clock.

In addition, when being heat-treated again in subsequent processing or final process, after not needing control hot-working The cooling velocity under cooling velocity, 450 DEG C to 400 DEG C of temperature region under 575 DEG C to 525 DEG C of temperature region.

(heat treatment)

The main heat treatment of copper alloy is also known as annealed, such as when being processed into the small size that can not be squeezed in hot extrusion, Its recrystallization is heat-treated and made as needed after cold stretch or cold-drawn wire, that is, usually so that the purpose that material softens And implement.Also, in hot-working material, also when such as needing the material almost without processing strain or it is set as metallographic appropriate When tissue, implement heat treatment as needed.

In the brass alloys containing Pb, also implement heat treatment as needed.In the brass containing Bi of patent document 1 In the case where alloy, it is heat-treated under conditions of 350~550 DEG C, 1~8 hour.

In the case where the alloy of present embodiment, firstly, if being kept under 525 DEG C or more and 575 DEG C of temperature below 15 minutes or more and 8 hours hereinafter, then tensile strength, ductility, corrosion resistance, impact characteristics, hot properties improve.But If being heat-treated under conditions of the temperature of material is more than 620 DEG C, many γ phases or β phase are formed instead, and become α phase It is coarse.As heat treatment condition, the temperature of heat treatment is preferably 575 DEG C or less.

On the other hand, although also can lower than 525 DEG C at a temperature of be heat-treated, the reduction degree of γ phase is sharply Reduce, it is therefore desirable to the time.At least at 505 DEG C more than and less than 525 DEG C at a temperature of need 100 minutes or more, preferably 120 Minute or more time.And lower than 505 DEG C at a temperature of be heat-treated for a long time, the reduction of γ phase can be made slightly to stop γ phase only or is hardly reduced, and occurs μ phase according to condition.

The time (time kept with the temperature of heat treatment) of heat treatment needs in 525 DEG C or more and 575 DEG C of temperature below It is at least kept under degree 15 minutes or more.Retention time facilitates the reduction of γ phase, therefore preferably 40 minutes or more, more preferably 80 minutes or more.The upper limit of retention time is 8 hours, and from economic considerations for 480 minutes hereinafter, preferably 240 minutes Below.Or as described, 505 DEG C or more, preferably 515 DEG C more than and less than 525 DEG C at a temperature of, be 100 minutes or more, Preferably 120 minutes or more and 480 minutes or less.

The advantages of as heat treatment at this temperature, when the amount of the γ phase of the material before heat treatment is less, by α phase, κ phase Softening rest on minimum limit, hardly happen α phase grain growth, higher intensity can be obtained.Also, facilitate intensity Exist at most in 515 DEG C or more and 545 DEG C of heat treatments below with 1 phase of κ of machinability.As 1 phase of κ is from the temperature liter The amount of high or reduction, 1 phase of κ is reduced, and there's almost no at 500 DEG C or less or 590 DEG C or more.

As another heat treatment method, when in hot extrusion material, warm and hot forging product, hot calender material or having carried out cold drawing Stretch, the continuous heat treating furnace that the material of the processing such as bracing wire moves in heat source in the case where, if material temperature is more than 620 DEG C, For problem as mentioned.But for the time being by the temperature of material promoted to 525 DEG C or more, be preferably 530 DEG C or more and 620 DEG C with Under, preferably 595 DEG C hereinafter, be then equivalent to 525 DEG C or more and 575 DEG C temperature regions below holdings 15 minutes or more Under the conditions of, that is, make the time kept under 525 DEG C or more and 575 DEG C of temperature regions below, pass through in cooling with after holding The time of 525 DEG C or more and 575 DEG C temperature regions below adds up to 15 minutes or more, and thus, it is possible to improve metallographic structure. It is shorter with the time that maximum temperature reached is kept in the case where continuous oven, therefore under 575 DEG C to 525 DEG C of temperature region Cooling velocity be preferably 0.1 DEG C/min or more and 3 DEG C/min hereinafter, more preferably 2 DEG C/min hereinafter, further preferably It is 1.5 DEG C/min or less.Certainly, it is not limited to 575 DEG C or more of set temperature, such as when maximum temperature reached is 545 DEG C When, 545 DEG C to 525 DEG C of temperature can also at least be kept 15 minutes or more.On the contrary, reaching temperature as highest when completely arriving at It is logical under conditions of becoming 1.3 DEG C/min of average cooling rates below when 545 DEG C of degree and its retention time are 0 minute Cross 545 DEG C to 525 DEG C of temperature region.That is, if kept for 20 minutes or more in 525 DEG C or more of temperature region, and In the range of 525 DEG C to 620 DEG C, then maximum temperature reached is not a problem.It is not limited to continuous oven, the definition of retention time is set as Time from reaching maximum temperature reached and subtracting 10 DEG C.

In these heat treatments, material is also cooled to room temperature, but in cooling procedure, is needed 450 DEG C to 400 DEG C of temperature Cooling velocity under degree region is set as 3 DEG C/min or more and 500 DEG C/min or less.Under 450 DEG C to 400 DEG C of temperature region Cooling velocity is preferably 4 DEG C/min or more.That is, it needs to nearby accelerate cooling velocity with 500 DEG C for boundary.In general, in furnace In cooling, the lower side of temperature, such as 550 DEG C to 430 DEG C one sides cooling velocity slow down.

(heat treatment of casting)

When final products are casting, the casting being cooled to room temperature after casting is also passed through into any in following (1)~(4) Condition heats copper alloy, is cooled down.

(3) temperature of material is increased to 525 DEG C or more and 620 DEG C hereinafter, then at 525 DEG C or more and 575 DEG C for the time being It is kept for 15 minutes or more under temperature region below, or

(4) under the conditions of comparable with above-mentioned (3), specifically by 525 DEG C or more and 575 DEG C of temperature regions below with 0.1 DEG C/min or more and 3 DEG C/min of average cooling rates below are cooled down.

Then, by 450 DEG C to 400 DEG C of temperature region with 3 DEG C/min or more and 500 DEG C/min average coolings below Speed is cooled down, and thus, it is possible to improve metallographic structure.

If with 2000 times or 5000 times of electron microscope observation metallographic structure, with the presence or absence of the cooling on the boundary of μ phase Speed is about 8 DEG C/min in 450 DEG C to 400 DEG C of temperature region.In particular, having the critical cold of larger impact to various characteristics But speed is about 3 DEG C/min or about 4 DEG C/min.Certainly, the appearance of μ phase also relies on composition, and Cu concentration is higher, Si concentration The value of higher, metallographic structure relational expression f1 is bigger, the quicker progress of the formation of μ phase.

That is, if the cooling velocity of 450 DEG C to 400 DEG C of temperature region is slower than 8 DEG C/min, the μ phase in crystal boundary is precipitated The length of long side reaches about 1 μm, as cooling velocity slows down and further growth.Moreover, if cooling velocity becomes about 5 DEG C/minute Clock, then the length of the long side of μ phase becomes about 10 μm from about 3 μm.If cooling velocity, which becomes, is approximately less than 3 DEG C/min, the length of μ phase The length on side is more than 15 μm, in some cases more than 25 μm.If the length of the long side of μ phase reaches about 10 μm, with 1000 times Metallurgical microscopes μ can be made to distinguish in grain boundary, thus allow for observing.On the other hand, the upper limit of cooling velocity Although different according to hot processing temperature etc., if cooling velocity is too fast, the composition formed under high temperature is mutually directly maintained to normal Temperature, κ phase increase, and influence corrosion resistance, the β phase of impact characteristics, γ phase and increase.

Currently, the brass alloys containing Pb account for the overwhelming majority of the extruded material of copper alloy.It is closed in the brass for containing Pb In the case where gold, as described in patent document 1, it is heat-treated as needed with 350~550 DEG C of temperature.350 DEG C of lower limit It is the temperature recrystallize and material substantially softens.Recrystallization is completed at 550 DEG C of the upper limit and crystal grain starts coarsening again. Also, there is a problem of on energy due to improving temperature, if also, being heat-treated with the temperature more than 550 DEG C, β phase It obviously increases.Accordingly, it is considered to which the upper limit is 550 DEG C.As general manufacturing equipment, batch furnace or continuous oven can be used, It is cold to reach from about 300 DEG C about 50 DEG C of laggard promoting the circulation of qi in the case where batch furnace, after furnace is cold.In the case where continuous oven, in material Material temperature degree is reduced to before about 300 DEG C, is cooled down with slow speed.With the manufacturing method of the alloy with present embodiment Different cooling velocities are cooled down.

The metallographic structure of alloy about present embodiment, in manufacturing process importantly, after heat treatment or heat plus Cooling velocity in cooling procedure after work under 450 DEG C to 400 DEG C of temperature region.When cooling velocity is less than 3 DEG C/min, μ Ratio shared by phase increases.μ phase is mainly formed centered on grain boundary, phase boundray.In the presence of a harsh environment, μ compares α phase, κ The poor corrosion resistance of phase, therefore become the selective etching of μ phase and the reason of grain boundary corrosion.Also, identically as γ phase, μ coordinates The reason of for stress raiser or as Grain Boundary Sliding, reduce impact characteristics and elevated temperature strength.Preferably after hot working cold But in, the cooling velocity under 450 DEG C to 400 DEG C of temperature region is 3 DEG C/min or more, preferably 4 DEG C/min or more, more excellent 8 DEG C/min or more are selected as, the upper limit is 500 DEG C/min hereinafter, preferably 300 DEG C/min or less.

(cold working process)

It is high-intensitive in order to obtain, it, can also be right in order to improve dimensional accuracy, or in order to make the coil being extruded become straight line Hot extrusion material implements cold working.Such as to hot extrusion material with about 2%~about 20%, preferably with about 2%~about 15%, more Cold stretch is preferably implemented with about 2%~about 10% working modulus, and implements to be heat-treated.Or hot place is then carried out in hot-working After reason, with about 2%~about 20%, preferably with about 2%~about 15%, more preferably with about 2%~about 10% working modulus reality Cold-drawn wire processing, calendering processing are applied, and applies correction process in some cases.For the size of final products, sometimes also It repeats to implement cold working and heat treatment.In addition, sometimes only by the straightness of correcting device raising bar or to the forging after hot-working It makes product and implements bead, substantive cold working rate is about 0.1%~about 1.5% or so, even if there is slight cold working rate, Intensity can be made to get higher.

The advantages of cold working is the intensity this point that can be improved alloy.By to hot-working combination of materials carry out 2%~ Cold working and heat treatment under 20% working modulus, even if its sequence on the contrary, can to obtain high intensity, ductility, impact special Property balance, can depending on the application and obtain pay attention to intensity, pay attention to ductility and toughness characteristic.

When implementing the heat treatment of present embodiment after working modulus is 2~15% cold working, filled by heat treatment Point restore α phase, κ phase this two-phase, but not perfect recrystallization, there is processing strain to remain in two-phase.γ phase is reduced simultaneously, and another On the one hand needle-shaped κ phase (1 phase of κ) is present in α phase and α phase enhances, and κ phase increases.As a result, ductility, impact characteristics, Tensile strength, hot properties, intensity/ductility balanced index are more than hot-working material, and equilibrium index f8 becomes 690 or more, Further become 700 or more.Alternatively, f9 reaches 715 or more, further reach 725 or more.By using this manufacturing process, The alloy of excellent corrosion resistance, impact characteristics, ductility, intensity and excellent in machinability can be made.

In addition, as free-cutting machinability copper alloy, in the copper alloy widely generally used, if implementing 2~15% Cold working after be heated to 505 DEG C~575 DEG C, then by recrystallization intensity decline to a great extent.That is, implementing showing for cold working Have in free-cutting copper alloy, is declined to a great extent by dynamic recrystallization treatment intensity, but implement the present embodiment of cold working Alloy rises intensity instead, and obtains very high intensity.In this way, implementing the alloy of the present embodiment of cold working and showing Free-cutting copper alloy is that the trace after heat treatment is entirely different.

(low-temperature annealing)

In bar, forged article, casting, mainly for removal residual stress and correction bar, sometimes in recrystallization temperature It spends at temperature below and low-temperature annealing is carried out to bar, forged article.In the case where the alloy of present embodiment, maintain tension strong Degree, and elongation, yield strength improve.As the condition of the low-temperature annealing, preferably by material temperature be set as 240 DEG C or more and 350 DEG C hereinafter, will be set as 10 minutes to 300 minutes heating time.And then the temperature (material temperature) of low-temperature annealing is set as T (DEG C), when will be set as t (minute) heating time, preferably meeting 150≤(T-220) × (t)^1/2The condition of≤1200 relationship Lower implementation low-temperature annealing.In addition, be set as opening from low 10 DEG C of the temperature (T-10) of temperature than reaching defined temperature T (DEG C) herein Begin, (measurement) is counted to heating time t (minute).

When the temperature of low-temperature annealing is lower than 240 DEG C, the removal of residual stress is not enough, and will not sufficiently be rectified Just.When the temperature of low-temperature annealing is more than 350 DEG C, μ phase is formed centered on grain boundary, phase boundray.If low-temperature annealing when Between less than 10 minutes, then the removal of residual stress is not enough.μ phase increases if being more than 300 minutes if the time of low-temperature annealing.With Improve the temperature of low-temperature annealing or increase the time, μ phase increases, so that corrosion resistance, impact characteristics and hot properties reduce.So And not can avoid the precipitation of μ phase by implementing low-temperature annealing, how to remove residual stress and is limited in the precipitation of μ phase most Small limit becomes key.

In addition, (T-220) × (t)^1/2Value lower limit be 150, preferably 180 or more, more preferably 200 or more.And And (T-220) × (t)^1/2The upper limit of value be 1200, preferably 1100 hereinafter, more preferably 1000 or less.

The high-strength simple-cutting copper alloy of of the invention the 1st, 2 embodiments is manufactured by this manufacturing method.

Hot procedure, heat treatment (also known as annealing) process, low-temperature annealing process are the work heated to copper alloy Sequence.When without low-temperature annealing process, or when carrying out hot procedure or heat treatment procedure after low-temperature annealing process (when low-temperature annealing process does not become in the process finally heated to copper alloy), independently with the presence or absence of cold working, heat The process carried out after in manufacturing procedure, heat treatment procedure becomes important.When carrying out hot procedure after heat treatment procedure Or (finally copper alloy is being heated when hot procedure becomes after hot procedure without heat treatment procedure when When process), hot procedure needs to meet above-mentioned heating condition and cooling condition.It is heat-treated when after hot procedure Process (adds copper alloy finally when heat treatment procedure becomes when after heat treatment procedure without hot procedure When the process of heat), heat treatment procedure needs to meet above-mentioned heating condition and cooling condition.For example, when after warm and hot forging process When without heat treatment procedure, warm and hot forging process needs to meet the heating condition and cooling condition of above-mentioned warm and hot forging.When being hot-forged It makes when carrying out heat treatment procedure after process, heat treatment procedure needs to meet the heating condition and cooling condition of above-mentioned heat treatment. In this case, warm and hot forging process will not necessarily meet the heating condition and cooling condition of above-mentioned warm and hot forging.

In low-temperature annealing process, material temperature be 240 DEG C or more and 350 DEG C hereinafter, the temperature with whether generate μ phase and have It closes, it is unrelated with temperature range (575~525 DEG C, 525~505 DEG C) of γ phase reduction.In this way, the material in low-temperature annealing process Temperature is unrelated with the increase and decrease of γ phase.Therefore, when after hot procedure or heat treatment procedure carry out low-temperature annealing process when (when Low-temperature annealing process becomes in the process finally heated to copper alloy), together with the condition of low-temperature annealing process, low temperature The fire-bar of process (process that copper alloy is heated before carrying out low-temperature annealing process immediately) before annealing operation Part and cooling condition become important, and the process before low-temperature annealing process and low-temperature annealing process needs to meet above-mentioned heating condition And cooling condition.Specifically, in the process before low-temperature annealing process, in hot procedure, heat treatment procedure, at this The heating condition and cooling condition of the process carried out after process also become important, need to meet above-mentioned heating condition and cooling item Part.When carrying out hot procedure or heat treatment procedure after low-temperature annealing process, as described in hot procedure, heat The process carried out in treatment process, after the process becomes important, needs to meet above-mentioned heating condition and cooling condition.In addition, Hot procedure or heat treatment procedure can also be carried out before or after low-temperature annealing process.

According to the free-cutting machinability alloy for being set as the first and second embodiments of the invention as constructed as above, advise as described above Composition of alloy, component relationship formula, metallographic structure, membership credentials formula are determined, therefore corrosion resistance in the presence of a harsh environment, impact spy Property and having excellent high-temperature strength.Also, even if the content of Pb is few, it can also obtain excellent machinability.

More than, embodiments of the present invention are illustrated, but the present invention is not limited to this, is not departing from its invention Technical requirements in the range of can suitably change.

Embodiment

The result of the confirmation experiment described below carried out to confirm effect of the invention.In addition, embodiment below For illustrating effect of the invention, documented constitutive requirements, process, condition and non-limiting technology model of the invention in embodiment It encloses.

(embodiment 1)

> is tested in < practical operation

The prototype test of copper alloy is implemented using the low frequency smelting furnace and semicontinuous casting machine that use in actual operation.Table Composition of alloy is shown in 2.In addition, also being carried out to impurity in the alloy shown in table 2 due to having used engineering equipment Measurement.Also, manufacturing process is set as condition shown in 5~table of table 11.

(process No.A1~A14, AH1~AH14)

The small base of diameter 240mm has been manufactured using the low frequency smelting furnace and semicontinuous casting machine of practical operation.Raw material uses According to the raw material of practical operation.Small base is cut into the length of 700mm and is heated.It carries out hot extrusion and is set as diameter The pole shape of 25.6mm is simultaneously wound into coil (extruded material).Then, by the adjustment of the heat preservation of coil and fan, at 575 DEG C ~525 DEG C of temperature region and 450 DEG C to 400 DEG C of temperature region carry out extruded material with 20 DEG C/min of cooling velocity It is cooling.It is also cooled down in 400 DEG C of temperature regions below with about 20 DEG C/min of cooling velocity.With the last of hot extrusion Temperature measuring is carried out centered on stage and using radiation thermometer, is determined from being squeezed out using extruder after about 3~4 seconds Extruded material temperature.In addition, the DS-06DF type radiation thermometer for having used Daido Steel Co., Ltd. to manufacture.

The average value of the temperature of the extruded material is confirmed as ± 5 DEG C of temperature shown in table 5,6 ((shown in table 5,6 Temperature) -5 DEG C~+5 DEG C of (temperature shown in table 5,6) in the range of).

In process No.AH14, temperature will be squeezed and be set as 580 DEG C.In the process other than process AH14, temperature will be squeezed It is set as 640 DEG C.Be in 580 DEG C of process No.AH14 squeezing temperature, the two kinds of materials prepared fail to squeeze out to last and It is abandoned.

After extrusion, correction is only implemented in process No.AH1.In process No.AH2, by the extrusion material of diameter 25.6mm Material cold drawing extends to diameter 25.0mm.

In process No.A1~A6, AH3~AH6, the extruded material cold drawing of diameter 25.6mm is extended into diameter 25.0mm. Is carried out by heating holding, and is changed with defined temperature, time for expanded material with the electric furnace of practical operation or the electric furnace in laboratory The average cooling rate or 450 DEG C to 400 DEG C of temperature region under 575 DEG C to 525 DEG C of temperature region of cooling procedure are become Under average cooling rate.

In process No.A7~A9, AH7~AH8, the extruded material cold drawing of diameter 25.6mm is extended into diameter 25.0mm. Expanded material is heat-treated with continuous oven, and changes maximum temperature reached, 575 DEG C to 525 DEG C of cooling procedure Temperature region under cooling velocity or 450 DEG C to 400 DEG C of temperature region under cooling velocity.

In process No.A10, A11, the extruded material of diameter 25.6mm is heat-treated.Then, in process In No.A10, A11, implement cold working rate be respectively about 5%, about 8% cold stretch, then corrected, make diameter respectively at It (stretched, corrected after heat treatment) for 25mm, 24.5mm.

Size after stretching in process No.A12 is φ 24.5mm, in addition to this, process identical with process No.A1.

In process No.A13, process No.A14 and process No.AH12, process No.AH13, the cooling after changing hot extrusion Speed, and change the cooling velocity under 575 DEG C to 525 DEG C of temperature region of cooling procedure or 450 DEG C to 400 DEG C Cooling velocity under temperature region.

As shown in Table 5,6, about heat treatment condition, the temperature of heat treatment is changed to 635 DEG C, when by keeping from 490 DEG C Between from 5 minutes change to 180 minutes.

In addition, in the following table, indicating the case where having carried out cold stretch before heat treatment with "○", indicate not carry out with "-" The case where.

About alloy No.1, molten metal is moved into holding furnace, adds it containing Sn, Fe, and implement process No.EH1, E1 and evaluated.

(process No.B1~B3, BH1~BH3)

The material (bar) of the diameter 25mm obtained in process No.A10 is cut to the length of 3m.Then, in template Upper arrangement bar, has carried out low-temperature annealing to correct purpose.Using low-temperature annealing condition at this time as condition shown in table 8.

In addition, the value of the conditional in table is the value of following formula.

(conditional)=(T-220) × (t)^1/2

T: temperature (material temperature) (DEG C), t: heating time (minute)

As a result, the poor linearity of only process No.BH1.Accordingly, with respect to the copper alloy made in process No.BH1, not Carry out the evaluation of characteristic.

(process No.C0, C1)

The ingot casting (small base) of diameter 240mm has been manufactured using the low frequency smelting furnace and semicontinuous casting machine of practical operation.Raw material The raw material according to practical operation is used.Small base is cut into the length of 500mm and is heated.Moreover, carrying out hot extrusion And it is set as the pole shape extruded material of diameter 50mm.The extruded material is extruded with straight rod shape in extrusion platform.Most with extruding Carry out temperature measuring centered on the stage and using radiation thermometer afterwards, determine from using extruder squeeze out when light about 3 Second~temperature of extruded material after 4 seconds.The average value for confirming the temperature of the extruded material is ± 5 of temperature shown in table 9 DEG C (in the range of+5 DEG C of -5 DEG C of (temperature shown in table 9)~(temperature shown in table 9)).In addition, 575 DEG C after squeezing out are extremely 525 DEG C of cooling velocity and 450 DEG C to 400 DEG C of cooling velocity are respectively 15 DEG C/min, 15 DEG C/min (extruded material).? In aftermentioned process, the extruded material (pole) obtained in process No.C0 forging raw material have been used as.In process No.C1, It is heated 60 minutes at 560 DEG C, 450 DEG C to 400 DEG C of cooling velocity is then set as 12 DEG C/min.

(process No.D1~D7, DH1~DH6)

The pole of the diameter 50mm obtained in process No.C0 is cut to the length of 180mm.The laterally disposed pole, Thickness is forged into as 16mm using 150 tons of pressure energy power of press of hot forging.Pass through about 3 after rigid warm and hot forging is at defined thickness Second~after about 4 seconds, the measurement of temperature has been carried out using radiation thermometer.Hot forging temperature (hot processing temperature) is confirmed as 10 institute of table The range of temperature ± 5 DEG C shown (in the range of+5 DEG C of -5 DEG C of (temperature shown in table 10)~(temperature shown in table 10)).

It in process No.D1~D4, DH2, DH6, is heat-treated with the electric furnace in laboratory, and changes the temperature of heat treatment Cooling speed under degree, time, the cooling velocity under 575 DEG C to 525 DEG C of temperature region and 450 DEG C to 400 DEG C of temperature region Degree is to implement.

In process No.D5, D7, DH3, DH4, heated 3 minutes with continuous oven with 565 DEG C to 590 DEG C, and change cooling speed Degree is to implement.

In addition, the temperature of heat treatment is the maximum temperature reached of material, as the retention time, uses and reach temperature in highest Spend the time kept into the temperature region of (- 10 DEG C of maximum temperature reached).

In process No.DH1, D6, DH5, in the cooling after warm and hot forging, change 575 DEG C to 525 DEG C and 450 DEG C to 400 DEG C temperature region under cooling velocity implement.In addition, finishing the production operation of sample with the cooling after forging.

< laboratory experiment >

The prototype test of copper alloy is implemented using laboratory equipment.Composition of alloy is shown in table 3 and table 4.In addition, remaining Part is Zn and inevitable impurity.The copper alloy of composition shown in table 2 is also used in laboratory experiment.Also, manufacture work Sequence is set as condition shown in 12~table of table 16.

(process No.E1, EH1)

In the lab, raw material is liquefied with defined ingredient ratio.By molten metal casting in diameter 100mm, length In the metal mold of 180mm, to make small base.In addition, also by one of molten metal from the smelting furnace for carrying out practical operation Divide and pour in the metal mold for casting from diameter 100mm, length 180mm, to make small base.The small base is heated, in process The pole of diameter 40mm is extruded as in No.E1, EH1.

Temperature measuring has been carried out using radiation thermometer after squeeze test machine just stops.As a result it is equivalent to from utilization and squeezes The temperature of about 3 seconds or the extruded material after 4 seconds from when machine squeezes out.

In process No.EH1, to squeeze out the production operation for finishing sample, resulting extruded material is in aftermentioned process In be used as warm and hot forging raw material.

In process No.E1, it is heat-treated after the extrusion with condition shown in table 12.

(process No.F1~F5, FH1, FH2)

The pole of the diameter 40mm obtained in process No.EH1 and aftermentioned process No.PH1 is cut into the length of 180mm Degree.The pole of laterally disposed process No.EH1 or the casting of process No.PH1, and forged using the press for being hot-forged 150 tons of pressure energy power Become 15mm at thickness.After rigid warm and hot forging is at defined thickness after about 3 seconds~4 seconds, carried out using radiation thermometer The measurement of temperature.Confirming hot forging temperature (hot processing temperature) is the range of temperature ± 5 DEG C shown in table 13 (in (13 institute of table The temperature shown) -5 DEG C~+5 DEG C of (temperature shown in table 13) in the range of).

By the cooling under the cooling velocity and 450 DEG C to 400 DEG C of temperature region under 575 DEG C to 525 DEG C of temperature region Speed is set to 20 DEG C/min, 18 DEG C/min.In process No.FH1, the pole obtained in process No.EH1 is implemented Warm and hot forging finishes the production operation of sample with cooling after warm and hot forging.

In process No.F1, F2, F3, FH2, warm and hot forging is implemented to the pole obtained in process No.EH1, is being hot-forged It is heat-treated after making.Change heating condition, the cooling velocity under 575 DEG C to 525 DEG C of temperature region and 450 DEG C to 400 DEG C temperature region under cooling velocity come implement heat treatment.

In process No.F4, F5, the casting (No.PH1) cast from metal mold is poured used as forging raw material and is carried out Warm and hot forging.Change heating condition, cooling velocity after warm and hot forging to implement heat treatment (annealing).

(process No.P1~P3, PH1)

In process No.PH1, by with defined ingredient than being liquefied the molten metal casting of raw material in internal diameter φ 40mm's In metal mold, to obtain casting.A part of molten metal is poured from the smelting furnace for carrying out practical operation and casts from internal diameter 40mm Metal mold in, to make casting.

In process No.PC, the continuously casting stick (not being recorded in table) of diameter phi 40mm is produced by continuously casting.

In process No.P1, heat treatment is implemented to the casting of process No.PH1, in process No.P2, P3, to process The casting of No.PC implements heat treatment.In process No.P1~P3, change heating condition, cooling velocity and implement hot place Reason.

In process No.R1, a part of molten metal poured from the smelting furnace for carrying out practical operation cast from 35mm × In the mold of 70mm.The surface of casting is subjected to face cutting and is set as 30mm × 65mm, which is heated to 780 DEG C, and real It applies the hot calender of 3 passages and thickness is made to become 8mm.After final hot calender, the material temperature after about 3~about 4 seconds is 640 DEG C, it is gas-cooled later.Then resulting calendering plate is heat-treated with electric furnace.

[table 2]

[table 3]

[table 4]

[table 5]

[table 6]

[table 7]

[table 8]

Conditional: (T-220) × (t)^1/2

T: temperature (DEG C), t: time (minute)

[table 9]

[table 10]

[table 11]

[table 12]

[table 13]

[table 14]

[table 15]

[table 16]

About above-mentioned test material, by following steps, to metallographic structure observation, corrosion resistance (Dezincification corrosion test/leaching Stain test), machinability evaluated.

(observation of metallographic structure)

It observes metallographic structure by the following method, and α phase, κ phase, β phase, γ phase, μ phase is determined by image analysis The area ratio (%).In addition, α ' phase, β ' phase, γ ' are mutually set as separately including in α phase, β phase, γ phase.

Bar, forged article for each test material, in parallel with longitudinal direction, or it is flat with the flow direction of metallographic structure It is cut off capablely.Then, surface is mirror-finished (mirror face polishing), and with hydrogen peroxide and ammonia The mixed liquor of water is etched.Used when etching by the ammonium hydroxide 22mL of the aquae hydrogenii dioxidi 3mL and 14vol% of 3vol% into The aqueous solution that row is obtained by mixing.At room temperature at about 15 DEG C~about 25 DEG C, the burnishing surface of metal is impregnated in about 2 in the aqueous solution Second~about 5 seconds.

Using metallurgical microscopes, metallographic structure is mainly observed with 500 times of multiplying power, and according to the situation of metallographic structure And metallographic structure is observed with 1000 times.In the microphoto of 5 visual fields, use image procossing software " Photoshop CC " Each phase (α phase, κ phase, β phase, γ phase, μ phase) is filled manually.Then, two are carried out by image analysis software " WinROOF2013 " Value, so as to find out the area ratio of each phase.Specifically, about each phase, the average value of the area ratio of 5 visual fields is found out, and Average value is set as to the phase ratio of each phase.Moreover, the total of all the area ratios for constituting phase is set as 100%.

The length of γ phase, the long side of μ phase is determined by the following method.Mainly use 500 times, the use when being difficult to differentiate 1000 times of metallurgical microscopes photo determines the maximum length of the long side of γ phase in 1 visual field.In arbitrary 5 visual fields In carry out the operation, calculate the average value of the long side maximum length of resulting γ phase, and be set as the length of the long side of γ phase.It is identical Ground using 500 times or 1000 times of metallic micrograph, or uses 2000 times or 5000 times of secondary electricity according to the size of μ phase Son determines the maximum length of the long side of μ phase as photo (electron micrograph) in 1 visual field.In arbitrary 5 visual fields The operation is carried out, the average value of the long side maximum length of resulting μ phase is calculated, and is set as the length of the long side of μ phase.

Specifically, being evaluated using about 70mm × about 90mm size photo is printed.In the feelings of 500 times of multiplying powers Under condition, the size for observing visual field is 220 μm of 276 μ m.

When the identification difficulty of phase, pass through FE-SEM-EBSP (electron backscattered slightly image (Electron Back Scattering Diffracton Pattern)) method, with 500 times or 2000 times of multiplying power to mutually being specified.

Also, in the embodiment for changing cooling velocity, it is precipitated whether there is or not main in the μ phase of grain boundary, makes to confirm The JSM-7000F manufactured with JEOL Ltd. shoots secondary electron under conditions of acceleration voltage 15kV, current value (setting value 15) Picture, and metallographic structure is confirmed with 2000 times or 5000 times of multiplying powers.When the secondary electron image that can use 2000 times or 5000 times When confirming μ phase, but cannot confirm μ phase with 500 times or 1000 times of metallic micrograph, non-reference area rate.That is, by 2000 times Or 5000 times of secondary electron image is observed but fails the μ phase confirmed in 500 times or 1000 times of metallic micrograph not Included in the area ratio of μ phase.This is because can not with metallurgical microscopes confirm μ phase be mainly long side length be 5 μm with Under, about 0.3 μm of width is hereinafter, therefore smaller to the influence of the area ratio.

The length of μ phase is measured in any 5 visual fields, as described being averaged the extreme length of 5 visual fields Value is set as the length of the long side of μ phase.The composition of μ phase is identified through attached EDS and carries out.In addition, when failing with 500 times or 1000 When confirming μ phase again, but determining the length of the long side of μ phase with higher multiplying power, the area ratio of μ phase in the measurement result in table Although being 0%, but still record the length of the long side of μ phase.

(observation of μ phase)

About μ phase, if after hot extrusion or after heat treatment, by 450 DEG C~400 DEG C of temperature region with 8 DEG C/min or 15 DEG C/min cooling velocity below is cooled down, then is able to confirm that the presence of μ phase.Fig. 1 shows test No.T05 (alloys No.S01/ process No.A3) secondary electron image an example.μ phase, which has been confirmed, in the grain boundary of α phase is precipitated that (lime color is elongated Phase).

(being present in the needle-shaped κ phase in α phase)

It is about 0.05 μm to about 0.5 μm that the needle-shaped κ phase (1 phase of κ) being present in α phase, which is width, and for it is elongated it is linear, Needle-shaped mode.If width is 0.1 μm or more, the presence of 1 phase of κ can be confirmed with metallurgical microscopes.

Fig. 2 indicates the metallic micrograph of test No.T73 (alloy No.S02/ process No.A1) as representative metal Microphoto.Fig. 3 indicates that the electron micrograph of test No.T73 (alloy No.S02/ process No.A1) is deposited as representative It is the electron micrograph of the needle-shaped κ phase in α phase.In addition, Fig. 2,3 observation position it is not identical.In copper alloy, Ke Nengyu The twin crystal for being present in α phase is obscured, but for the κ phase being present in α phase, the width of κ phase itself is narrow, and it is 1 group that twin crystal, which is two, Therefore them can be distinguished.In the metallic micrograph of Fig. 2, the needle-shaped pattern of elongated linear can be observed in α phase Phase.In the secondary electron image (electron micrograph) of Fig. 3, clearly confirming the pattern being present in α phase is κ phase.κ phase With a thickness of about 0.1~about 0.2 μm.

The amount (number) of the needle-shaped κ phase in α phase has been judged with metallurgical microscopes.Judgement (the metallographic structure of phase is constituted in metal Observation) in using captured 500 times or 5 visual fields under 1000 times of multiplying powers microphoto.It is about printing lengthwise 70mm, the horizontally long size for being about 90mm amplification visual field in, measure the quantity of needle-shaped κ phase, and found out being averaged for 5 visual fields Value.When average value of the quantity of needle-shaped κ phase in 5 visual fields be 20 more than and less than 70 when, be judged as substantially sufficiently have needle Shape κ phase, and it is denoted as " △ ".When average value of the quantity of needle-shaped κ phase in 5 visual fields is 70 or more, being judged as has many Needle-shaped κ phase, and it is denoted as "○".When average value of the quantity of needle-shaped κ phase in 5 visual fields is 19 or less, it is judged as and does not have Needle-shaped κ phase or needle-shaped κ phase there is no sufficient amount, and it is denoted as "×".Can not with photo confirm 1 phase of needle-shaped κ quantity not It is included.

(mechanical property)

(tensile strength)

Each test material is processed into No. 10 test pieces of JIS Z 2241, to carry out the measurement of tensile strength.If Do not include be cold worked process hot extrusion material or hot forged material tensile strength be 550N/mm²It above, is preferably 580N/mm² Above, it is more preferably 600N/mm²It above, is most preferably 625N/mm²More than, then it is also highest water in free-cutting machinability copper alloy Standard, so as to realize being thinning of the component used in each field/lightweight or increase allowable stress.

In addition, the alloy of present embodiment is the copper alloy with high-tensile, therefore the finished surface of tension test piece is thick Rugosity, which assigns elongation or tensile strength, to be influenced.Therefore, tension test piece is produced in a manner of meeting following conditions.

(condition of the completion surface roughness of tension test piece)

In the cross section curve of every datum length 4mm of any position between the punctuate of tension test piece, the maximum value of Z axis with The difference of minimum value is 2 μm or less.Cross section curve refers to, the low-pass filter of cutoff value λ s is suitable for measurement cross section curve and is obtained Curve.

(high-temerature creep)

Go out flanged (FLGD) test piece of the diameter 10mm of JIS Z 2271 according to each specimen preparation.It determines and will be equivalent to room The load of 0.2% yield strength of temperature is applied in the state of test piece, the creep strain at 150 DEG C after 100 hours.With Elongation application between punctuate under 0.2% yield strength, that is, room temperature is equivalent to the load of 0.2% plastic deformation, if applying Having added the creep strain after keeping test piece 100 hours at 150 DEG C in the state of the load is 0.3% hereinafter, being then good It is good.If the creep strain be 0.2% hereinafter, if be highest level in copper alloy, for example, can use at high temperature Valve, close to engine room automobile component in, the material as high reliablity.

(impact characteristics)

In impact test, from extruded bars, forged material and its alternative materials, founding materials, continuously casting bar Have chosen the U-shaped notch bar (notch depth 2mm, notched bottoms radius 1mm) according to JIS Z 2242.With rushing for radius 2mm It hits sword and carries out Charpy-type test, and determine impact value.

In addition, the relationship of impact value when being carried out with notch V test piece and U-shaped notch bar approximately as.

(notch V impact value)=0.8 × (U-shaped recess impact value) -3

(machinability)

As the evaluation of machinability, the cutting test for having used lathe is evaluated as follows.

To the hot extrusion bar of diameter 50mm, 40mm or 25.6mm, the cold stretch material of diameter 25mm (24.5mm) and casting Part implements machining and produces the test material of diameter 18mm.Machining is implemented to forged material and produces diameter 14.5mm test material.It, especially will be without the carbon of chip-breaker by tip straight tool (point nose straighttool) Change tungsten Cutting tool installation manner on lathe.Using the lathe, under dry conditions, and preceding nose angle -6 degree, nose radius 0.4mm, cut Speed is cut 150m/ minutes, under conditions of cutting depth 1.0mm, feed speed 0.11mm/rev, in diameter 18mm or diameter It is cut on the circumference of the test material of 14.5mm.

From the dynamometer for 3 parts for including the tool that is installed on, (MIHODENKI CO., LTD. manufacture, AST formula tool are surveyed Power meter AST-TL1003) signal that issues is converted to electrical voltage signal (electrical voltage signal), and it records In a recorder.Then, these signals are converted into cutting resistance (N).Therefore, by measurement cutting resistance especially cutting when The main component for showing peak, evaluates the machinability of alloy.

Chip is chosen simultaneously, and machinability is evaluated by Chip Shape.Become in the cutting of actual use Greatest problem, chip is wrapped with tool or the volume of chip is larger.Therefore, it will only generate a Chip Shape and be volume 1 and below cut The case where bits, is evaluated as "○" (good (good)).It will be evaluated the case where generating the chip until Chip Shape is more than volume 1 and volume 3 For " △ " (fair (fine)).The case where Chip Shape is more than the chip of volume 3 will be generated and be evaluated as "×" (poor (bad)).This Sample has carried out the evaluation in 3 stages.

Cutting resistance also relies on the intensity of material, such as cuts stress, tensile strength and 0.2% yield strength, has The higher tendency of the higher material cutting resistance of intensity.If the cutting resistance with the free-cutting brass stick of the Pb containing 1~4% It compares, cutting resistance is higher by the degree of about 10% to about 20%, then is sufficiently allowed in actual use.In present embodiment, Cutting resistance is evaluated as boundary (boundary value) using 130N.Specifically, if cutting resistance be 130N hereinafter, if evaluate For excellent in machinability (evaluation: zero).If cutting resistance be more than 130N and for 150N hereinafter, if machinability is evaluated as " still (△)".If cutting resistance is more than 150N, it is evaluated as " bad (×) ".In addition, to 58 mass %Cu-42 mass %Zn alloys Implement process No.F1 come make sample and evaluate as a result, cutting resistance be 185N.

(hot-working test)

By the bar of diameter 50mm, diameter 40mm, diameter 25.6mm or diameter 25.0mm and by cutting make casting at For diameter 15mm, and length 25mm is cut into produce test material.Test material is maintained at 740 DEG C or 635 DEG C 15 minutes.Then, placed longitudinally test material, and use with 10 tons of hot compression ability and be equipped with the Amsler test of electric furnace Machine, carried out under rate of straining 0.02/ second, working modulus 80% it is high temperature compressed, so that thickness be made to become 5mm.

About the evaluation of hot-workability, when the magnifying glass using 10 times of multiplying powers observes rupture of the 0.2mm with upper opening, It is judged as generation rupture.Will 740 DEG C, 635 DEG C the two under the conditions of do not generate rupture the case where be evaluated as "○" (good). Rupture will be produced at 740 DEG C but will be evaluated as " △ " (fair) the case where not generating rupture at 635 DEG C.It will be at 740 DEG C Rupture is not generated but is evaluated as " ▲ " (fair) the case where producing rupture at 635 DEG C.Will 740 DEG C, 635 DEG C the two The case where rupture is generated under part is evaluated as "×" (poor).

740 DEG C, 635 DEG C the two under the conditions of do not generate rupture when, about the hot extrusion and hot forging in actual use It makes, for implementing aspect, even if some material temperature declines occur, though also, even if metal mold or mold and material are winks When but have the temperature of contact and material decline, there is no problem in actual use as long as implementing at a proper temperature.When At any temperature in 740 DEG C and 635 DEG C generate rupture when, be judged as and hot-working can be implemented, but in actual use by Considerable restraint and need to be managed with narrower temperature range.When 740 DEG C, 635 DEG C both at a temperature of generate rupture when, It is judged as in actual use there is big problem, is bad.

(riveting (bending) processability)

In order to evaluate riveting (bending) processability, the periphery of bar, forged material is cut and becomes outer diameter Length with the bit bore of diameter phi 10mm, and is cut into 10mm by 13mm.In the above manner, producing outer diameter 13mm, thickness Spend the cylinder shaped test piece of 1.5mm, length 10mm.The sample is sandwiched in vice, its flat ovalisation is made by manpower, and Crack-free is investigated.

Riveting rate (flat ratio) when generating rupture is calculated by following formula.

(riveting rate)=(1- (length of the short side of the inside after flat)/(internal diameter)) × 100 (%)

(length (mm) of the short side of the inside after flat)=(length of the short side in the elliptical outside after flat)- (wall thickness) × 2

(internal diameter (mm))=(outer diameter of cylinder)-(wall thickness) × 2

In addition, keeping its flat cylindric material applied force, and attempt to revert to by rebound originally when unloading sanction Shape, referred to herein as the shape of permanent deformation.

Herein, when the riveting rate (bending machining rate) when generating rupture is 30% or more, by riveting (bending) processability It is evaluated as "○" (good, good).When riveting rate (bending machining rate) be 15% more than and less than 30% when, by riveting (bending) Processability is evaluated as " △ " (still, fair).When riveting rate (bending machining rate) is less than 15%, by riveting (bending) processability It is evaluated as "×" (bad, poor).

In addition, being riveted with the commercially available free-cutting brass stick (59%Cu-3%Pb- remainder Zn) added with Pb Test as a result, riveting rate be 9%.The conjunction accessory for having excellent free-cutting machinability has certain brittleness.

(Dezincification corrosion test 1)

When test material is extruded material, so that test material exposes the specimen surface side vertical with direction is squeezed out to the open air Formula injects test material in phenolic resin material.When test material is casting material (cast rod), so that test material It exposes the specimen surface mode vertical with the longitudinal direction of casting material to the open air, test material is injected in phenolic resin material.Work as examination Test material be forged material when, to make the specimen surface mode vertical with the flow direction of forging that expose to the open air of test material inject phenol In urea formaldehyde material.

By specimen surface by polishing to No. 1200 silicon carbide papers, then, ultrasonic cleaning is carried out in pure water And it is dried with air blower.Later, each sample is impregnated in prepared maceration extract.

After the test, so that exposed surface is vertical with the flow direction holding for squeezing out direction, longitudinal direction or forging Sample is re-injected into phenolic resin material by mode.Then, so that the section in corrosion portion is obtained as longest cutting portion The mode obtained cuts off sample.Then sample is polished.

Using metallurgical microscopes, with 500 times of multiplying power to corruption in microscopical 10 visual fields (arbitrary 10 visual fields) Erosion depth is observed.Most deep hot spot is registered as maximum Dezincification corrosion depth.

In Dezincification corrosion test, as maceration extract, following tests liquid is prepared, and implement aforesaid operations.

Commercially available medicament is put into distilled water and experimental liquid is adjusted.Assuming that the tap water that corrosivity is high, and Chloride ion 80mg/L, sulfate ion 40mg/L and nitrate ion 30mg/L are put into.Basicity and hardness are with Japan one As tap water on the basis of adjust separately as 30mg/L, 60mg/L.In order to which pH is reduced to 6.5, carbon dioxide is carried out on one side Flow adjustment is put on one side, in order to be saturated oxyty, has put into oxygen often.Water temperature be 25 DEG C ± 5 DEG C (20~ 30 DEG C) under carry out.If can speculate about 50 times of accelerated test under the corrosive environment severe as this using the solution. As long as maximum corrosion depth be 50 μm hereinafter, as long as corrosion resistance it is good.When requiring excellent corrosion resistance, maximum corruption can be speculated Losing depth is preferably 35 μm hereinafter, further preferably 25 μm or less.In the present embodiment, commented based on these guess values Valence.

In addition, sample is maintained 3 months in experimental liquid.Then, sample is taken out from aqueous solution, and it is de- to determine it The maximum value (maximum Dezincification corrosion depth) of zine corrosion depth.

(Dezincification corrosion tests the test of 2:ISO6509 Dezincification corrosion)

This test is used as Dezincification corrosion test method by many countries, also with JIS H3250 in JIS standard Regulation.

Test material is filled in phenolic resin material identically as Dezincification corrosion test.Each sample is impregnated in 1.0% copper chloride dihydrate (CuCl₂·2H₂O it in aqueous solution (12.7g/L)), is maintained under the conditions of 75 DEG C of temperature 24 hours.Later, sample is taken out from aqueous solution.

To make exposed surface keep vertical mode with the flow direction for squeezing out direction, longitudinal direction or forging, by sample It is re-injected into phenolic resin material.Then, it is cut in a manner of obtaining the section in corrosion portion as longest cutting portion Disconnected sample.Then sample is polished.

Using metallurgical microscopes, corrosion depth is carried out in microscopical 10 visual fields with 100 times or 500 times of multiplying power Observation.Most deep hot spot is registered as maximum Dezincification corrosion depth.

In addition, when carry out ISO 6509 test when, if maximum corrosion depth be 200 μm hereinafter, if become actually make With to the corrosion resistance level that there is no problem.Especially when requiring excellent corrosion resistance, it is preferred to be set as maximum corrosion depth For 100 μm hereinafter, further preferably 50 μm or less.

In this test, the case where by maximum corrosion depth being more than 200 μm, is evaluated as "×" (poor).By maximum corrosion depth " △ " (fair) is evaluated as more than the situation of 50 μm and 200 μm or less.The situation for being 50 μm or less by maximum corrosion depth is stringent Ground is evaluated as "○" (good).Present embodiment uses stringent evaluation criteria to assume severe corrosive environment, only It is good that the case where being evaluated as "○", is considered as corrosion resistance.

Show the results of the evaluation 17~table of table 55.

No.T01~T62, T71~T114, T121~T169 are tested as the result in the experiment of practical operation.Test No.T201~T208 makes the molten metal of practical operation furnace contain Sn, Fe and intentionally adding.Test No.T301~ The result for being equivalent to embodiment in the experiment in the laboratory T337.Test the phase in the experiment that No.T501~T537 is laboratory When in the result of comparative example.

In addition, the length of the long side about the μ phase in table, value " 40 " 40 μm of expressions or more.Also, about the γ phase in table Long side length, value " 150 " indicates 150 μm or more.

[table 17]

[table 18]

[table 19]

[table 20]

[table 21]

[table 22]

[table 23]

[table 24]

[table 25]

[table 26]

[table 27]

[table 28]

[table 29]

[table 30]

[table 31]

[table 32]

[table 33]

[table 34]

[table 35]

[table 36]

[table 37]

[table 38]

[table 39]

[table 40]

[table 41]

[table 42]

[table 43]

[table 44]

[table 45]

[table 46]

[table 47]

[table 48]

[table 49]

[table 50]

[table 51]

[table 52]

[table 53]

[table 54]

[table 55]

The above experimental result is summarized as follows.

1) be able to confirm that the composition by meeting present embodiment, and meet component relationship formula f1, f2, metallographic structure is wanted Part and membership credentials formula f3, f4, f5, f6, thus by obtaining good machinability containing a small amount of Pb, and obtain having good Excellent corrosion resistance under good hot-workability, rugged environment, and with high-intensitive, good ductility, impact characteristics, The hot extrusion material of bendability and hot properties, hot forged material (for example, alloy No.S01, S02, S13, process No.A1, C1、D1、E1、F1、F4)。

2) corrosion resistance (alloy being able to confirm that under conditions of being further improved and containing Sb, As badly No.S51,S52).But containing excessive Sb, As, the improvement effect of corrosion resistance is also saturated, ductility (elongation), impact Characteristic, hot properties are deteriorated (alloy No.S51, S52, S116) instead.

3) it is able to confirm that, due to containing Bi, cutting resistance further decreases (alloy No.S51).

4) it is able to confirm that intensity rises by making in α phase there are needle-shaped κ phase i.e. 1 phase of κ, it is intensity/elongation balance f8, strong Degree/elongation/impact balance f9 is got higher, and machinability is maintained well, and corrosion resistance, hot properties improve.In particular, if κ 1 The amount of phase increases, then the raising of intensity becomes obviously, even if γ phase is 0%, can also ensure that good machinability (such as alloy No.S01、S02、S03)。

If 5) Cu content is few, γ phase increases, and machinability is good, but corrosion resistance, ductility, impact characteristics, bending plus Work, hot properties are deteriorated.On the contrary, machinability is deteriorated if Cu content is more.Also, ductility, impact characteristics and bending machining Property also be deteriorated (alloy No.S102, S103, S112 etc.).

If 6) Si content less than 3.05 mass %, κ 1 phase there are insufficient, therefore tensile strength is low, and machinability is poor, Hot properties is also poor.If the amount that Si content is greater than 3.55 mass %, κ phases becomes excessively, and 1 phase of κ also exists too much, because This elongation is low, and processability, impact characteristics, machinability are poor, and tensile strength is also saturated (alloy No.S102, S104, S113).

If 7) P content is more, impact characteristics, ductility, tensile strength, bendability are deteriorated.On the other hand, if P contains Amount is few, then the Dezincification corrosion depth under adverse circumstances is big, and intensity is low, and machinability is also poor.F8, f9 are low in any situation.If Pb Content it is more, then machinability improve, but hot properties, ductility, impact characteristics be deteriorated.If the content of Pb is few, cutting resistance Increase, Chip Shape is deteriorated (alloy No.S108, S110, S118, S111).

If 8) contain a small amount of Sn or Al, γ phase is slightly increased, but impact characteristics, hot properties are slightly deteriorated, elongation Become slightly lower.Think to be enriched with Sn or Al on phase boundray etc..In addition, if the content of Sn or Al increases and respectively more than 0.05 matter The total content for measuring % or Sn and Al is more than 0.06 mass %, then γ phase increases, to impact characteristics, elongation, hot properties Influence becomes obviously, and corrosion resistance is deteriorated, and tensile strength also reduces (alloy No.S01, S11, S12, S41, S114, S115).

9) it is able to confirm that even if the inevitable impurity containing the degree being present in practical operation, it will not larger shadow It rings various characteristics (alloy No.S01, S02, S03).If thinking the composition near the boundary value containing present embodiment, but it is more than The Fe or Cr of the preferred scope of inevitable impurity, then form between the intermetallic compound of Fe and Si or the metal of Fe and P and change Object is closed, as a result, the Si concentration of useful effect, P concentration are reduced, the amount of 1 phase of κ is reduced, and corrosion resistance is slightly deteriorated, and intensity is decreased slightly as It is low.Formation interaction with intermetallic compound and cutting ability, impact characteristics, cold-workability be decreased slightly as it is low (alloy No.S01, S13、S14、S117)。

If 10) value of component relationship formula f1 is low, γ phase increases, and also occurs β phase sometimes, and machinability is good, but corrosion resistant Corrosion, impact characteristics, cold-workability, hot properties are deteriorated.If the value of component relationship formula f1 is high, κ phase increases, can also go out sometimes Existing μ phase, machinability, cold-workability, hot-workability, impact characteristics are deteriorated (alloy No.S103, S104, S112).

If 11) value of component relationship formula f2 is low, the amount of γ phase increases, and occurs β phase in some cases, machinability is good It is good, but hot-workability, corrosion resistance, ductility, impact characteristics, cold-workability, hot properties are deteriorated.In particular, alloy No.S109 Although meeting whole composition important documents other than f2, hot-workability, corrosion resistance, ductility, impact characteristics, cold working Property, hot properties are poor.If the value of component relationship formula f2 is high, although Si content is more, 1 phase of κ there are insufficient or less, because This tensile strength is low, and hot-workability is poor.And being speculated as the formation of coarse α phase and the amount of 1 phase of κ is main cause less, cutting Resistance is big, and the segmentation of chip is also poor.Although being wanted in particular, alloy No.S105~S107 meets whole compositions other than f2 The major part of part, relational expression f3~f6, but tensile strength is low, and machinability is poor (alloy No.S109, S105~S107).

12) it in metallographic structure, if the length that the ratio of γ phase is greater than the long side of 0.3% or γ phase is greater than 25 μm, cuts Cutting property is good, but intensity is low, corrosion resistance, ductility, cold-workability, impact characteristics, hot properties be deteriorated (alloy No.S101, S102).If the ratio of γ phase is 0.1% or less, is further 0%, corrosion resistance, impact characteristics, cold-workability, room temperature and Elevated temperature strength becomes good (alloy No.S01, S02, S03).

When the length that the area ratio of μ phase is greater than the long side of 1.0% or μ phase is more than 20 μm, corrosion resistance, ductility, punching Characteristic, cold-workability, hot properties is hit to be deteriorated.(alloy No.S01, process No.AH4, BH2, DH2).If the ratio of μ phase is The length of the long side of 0.5% or less and μ phase is 15 μm hereinafter, then corrosion resistance, ductility, impact characteristics, room temperature and high temperature are special Property become good (alloy No.S01, S11).

If the area ratio of κ phase is greater than 60%, machinability, ductility, bendability, impact characteristics are deteriorated.Another party Face, if the area ratio of κ phase is less than 29%, tensile strength is low, and machinability is poor (alloy No.S104, S113).

13) when membership credentials formula f5=(γ)+(μ) is more than 1.2% or when f3=(α)+(κ) is less than 98.6%, corrosion resistant Corrosion, ductility, impact characteristics, bendability, room temperature and hot properties are deteriorated.If membership credentials formula f5 be 0.5% hereinafter, Then corrosion resistance, ductility, impact characteristics, room temperature and hot properties become it is good (alloy No.S01, process No.AH2, FH1, A1、F1)。

If membership credentials formula f6=(κ)+6 × (γ)^1/2+ 0.5 × (μ) is greater than 62 or less than 30, then machinability is poor.In addition, With same composition and in the alloy of different processes manufacture, even if if κ 1 under the value in f6 is identical or higher situation The case where amount of phase is less, then cutting resistance is also larger or identical, and there is also the segmentation of chip variation (alloy No.S01, S02, S104, S113, process No.A1, AH5~AH7, AH9~AH11).

14) satisfaction all form important document, metallographic structure important document and be not carried out cold working hot extrusion material or In forged material, the Charpy-type test value of U-shaped recess is 15J/cm²More than, most of is 16J/cm²More than.Tensile strength is equal For 550N/mm²More than, most of is 580N/mm²More than.κ phase is about 33% or more, if 1 phase of κ exists more, there is also Tensile strength is about 590N/mm²Above and 620N/mm²Above warm and hot forging product.Moreover, intensity/elongation equilibrium index f8 It is 675 or more, most of is 690 or more.Intensity/elongation/impact equilibrium index f9 is more than 700, most of more than 715, Achieve the balance (alloy No.S01, S02, S03, S23, S27) between intensity and ductility.

As long as 15) meet the important document of the important document, metallographic structure that all form, U is ensured and the combination with cold working The Charpy-type test value of shape recess is 12J/cm²More than, tensile strength 600N/mm²Above and display is high-intensitive, and balance refers to Number f8 is 690 or more, and most of be 700 or more, f9 be 715 or more, most of for 725 or more (alloy No.S01, S03, processes No.A1, A10~A12).

16) in the relationship between tensile strength and hardness, implement process in the composition to alloy No.S01, S03, S101 No.F1 and in the alloy that makes, tensile strength 602N/mm²、625N/mm²、534N/mm², hardness HRB is respectively 84,88, 68。

17) when Si amount is about 3.05% or more, come into existence needle-shaped 1 phase of κ (△) in α phase, and Si amount is about 3.15% or more When, (zero) is significantly increased in 1 phase of κ.Relational expression f2 influence 1 phase of κ amount, if f2 be 61.0 hereinafter, if 1 phase of κ increase.

If the amount of 1 phase of κ increases, machinability, tensile strength, hot properties, intensity/elongation/impact balance become Well.The raising of the enhancing and machinability that can speculate α phase is main cause (alloy No.S01, S02, S26, S29 etc.).

18) in the test method of ISO6509, the alloy of the β phase containing about 1% or more or the γ phase containing about 5% or more For unqualified (evaluation: △, ×), but the alloy of the γ phase containing about 3% or the μ phase containing about 3% is qualified (evaluation: zero). Corrosive environment employed in present embodiment has been based on the assumption that adverse circumstances (alloy No.S01, S26, S103, S109 etc.).

19) substantially phase has been obtained in the evaluation of manufactured material in the material for having used volume production equipment and in the lab Same result (alloy No.S01, S02, process No.C1, E1, F1).

20) about manufacturing condition:

If below at 525 DEG C or more and 575 DEG C by hot extrusion material, the material for being extruded/stretching, hot forged material Kept for 15 minutes in temperature region or more, or 505 DEG C more than and less than 525 DEG C at a temperature of kept for 100 minutes or more, or In continuous oven, cooled down under 525 DEG C or more and 575 DEG C of temperature below with 3 DEG C/min of cooling velocities below, then 450 DEG C to 400 DEG C of temperature region is cooled down with 3 DEG C/min or more of cooling velocity, then available γ phase substantially subtracts Less, the corrosion resistance of μ phase, ductility, hot properties, impact characteristics, cold-workability and mechanical strength be there's almost no Material (process No.A1, A5, A8).

In the process being heat-treated to hot-working material and cold working material, if the temperature low (490 DEG C) of heat treatment, Or 505 DEG C more than and less than 525 DEG C at a temperature of heat treatment in the retention time it is short, then the reduction of γ phase is less, 1 phase of κ Amount is few, corrosion resistance, impact characteristics, ductility, cold-workability, hot properties, intensity/ductility/impact balanced differences (process No.AH6,AH9,DH6).If the temperature of heat treatment is high, the crystal grain of α phase is become thick, and κ 1 is mutually few, and the reduction of γ phase is less, because This corrosion resistance, cold-workability are poor, and machinability is also poor, and tensile strength is also low, f8, f9 also low (process No.AH11, AH6).

If by hot forged material, extruded material 515 DEG C or 520 DEG C at a temperature of, carried out with 120 minutes or more long-times Heat treatment, then γ phase is greatly decreased, and the amount of 1 phase of κ is also more, and the reduction of elongation and impact value is limited in minimum limit, resists Tensile strength is got higher, and hot properties, f8, f9 are also improved, thus the valve that requires pressure-resistant performance on the way most preferably (process No.A5, D4、F2)。

In cooling after heat treatment, if the cooling velocity under 450 DEG C to 400 DEG C of temperature region is slow, there are μ phase, Corrosion resistance, impact characteristics, ductility, hot properties are poor, and tensile strength is also low (process No.A1~A4, AH8, DH2, DH3).

As heat treatment method, temperature is improved to 525 DEG C~620 DEG C for the time being, slows down 575 DEG C in cooling procedure extremely Cooling velocity under 525 DEG C of temperature region, thus γ phase be greatly decreased or become 0%, and obtain good corrosion resistance, Impact characteristics, cold-workability, hot properties.The improvement of characteristic is also confirmed in continuous heat processing method.(process No.A7~ A9、D5)。

In cooling after warm and hot forging, after hot extrusion, by by the cooling velocity under 575 DEG C to 525 DEG C of temperature region Control is 1.6 DEG C/min, the few forged article (process No.D6) of ratio shared by the γ phase after obtaining warm and hot forging.Also, even if Use casting as warm and hot forging raw material, also using identical obtains good various characteristics with extruded material.(process No.F4,F5).If casting is heat-treated under suitable condition, the few casting (process of ratio shared by γ phase is obtained No.P1~P3).

If hot calender material is heat-treated under suitable condition, the few calendering material of ratio shared by γ phase is obtained Expect (process No.R1).

If defined heat treatment is carried out after applying the cold working that working modulus is about 5%, about 8% to extruded material, with heat Extruded material is compared, and corrosion resistance, impact characteristics, hot properties, tensile strength improve, and especially tensile strength improves about 60N/ mm², about 70N/mm², equilibrium index f8, f9 also improves about 70~about 80 (process No.AH1, A1, A12).

If heat treatment material is processed with cold working rate 5%, compared with extruded material, tensile strength is improved about 90N/mm², f8, f9 raising about 100, corrosion resistance, hot properties also increase.If cold working rate is set as about 8%, resist Tensile strength improves about 120N/mm², f8, f9 improve about 120 (process No.AH1, A10, A11).

If implementing heat treatment appropriate, there can be needle-shaped κ phase (process No.A1, D7, C1, E1, F1) in α phase.It can speculate By the presence of 1 phase of κ, tensile strength is improved, and machinability is also good, compensates for being greatly decreased for γ phase.

Be able to confirm that after cold working or after hot-working carry out low-temperature annealing in the case where, with 240 DEG C or more and 350 DEG C with Under temperature heat 10 minutes to 300 minutes, when heating temperature is set as T DEG C, will be set as heating time t minutes, if with 150≤ (T-220)×(t)^1/2≤ 1200 condition is heat-treated, then can obtain having excellent corrosion-resistant under rugged environment Property, with good impact characteristics, the cold working material of hot properties, hot-working material (alloy No.S01, process No.B1~ B3)。

In the sample for implementing process No.AH14 to alloy No.S01, S02, due to deformation drag height, fail to squeeze out extremely Finally, the evaluation after therefore having ceased.

In process No.BH1, the insufficient and low-temperature annealing of correction is inappropriate, to lead to the problem of in quality.

According to above situation, as the alloy of present embodiment, the content of each addition element and each composition relational expression, gold The hot-workability (hot extrusion, warm and hot forging) of the alloy of the present embodiment of phase constitution, each tissue relational expression in appropriate range It is excellent, and corrosion resistance, machinability are also good.Also, it, can in order to obtain excellent characteristic in the alloy of present embodiment It is realized by the way that the manufacturing condition in hot extrusion and warm and hot forging, the condition in heat treatment are set as proper range.

Industrial availability

The hot-workability (hot extrusion and warm and hot forging) of free-cutting machinability copper alloy of the invention is excellent, and machinability is excellent Different, the high-intensitive lower balance between elongation or impact characteristics, hot properties, excellent corrosion resistance.Therefore, present embodiment Free-cutting machinability copper alloy be suitable for the utensil used in the drinking water of the every daily ingestion of humans and animals such as tap, valve, connector； Valve, connector etc. be electrical/automobile/machinery/industrial piping-member；It is contacted under room temperature, high temperature, low temperature with high pressure gas, liquid Valve, connector, utensil, component；And contacted with hydrogen valve, connector, utensil, in component.

Specifically, can suitably be applicable in as drinking water, draining, industrial water institute flowing water faucet accessory, mixing Formula tap accessory, drainage fitting, faucet body, hot-warer supplying machine component, water heater (Eco Cute) component, hose fitting, Water jet, water meter, plug, fire hydrant, hose coupling, supply and discharge water cock (cock), pump, header (header), pressure reducing valve, valve Seat, gate valve, valve, valve rod, fitting union (union), flange, divide water cock (corporation cock), faucet valve, ball valve, Various valves, constituent material of pipe-fitting joint etc., such as with bend pipe, socket, flat cylinder (cheese), elbow, connector, adapter, T The titles such as shape pipe, connector (joint) use.

Further, it is possible to be suitably applicable to the solenoid valve used as automobile component, control valve, various valves, radiator portion Part, oil cooler component, cylinder, as the pipe-fitting joint of mechanical component, valve, valve rod, heat exchanger component, water supply and sewage rotation Plug, cylinder, pump, in pipe-fitting joint, valve, valve rod as industrial piping-member etc..

It can also be preferably adapted for valve relevant to hydrogen, connector, the pressure vessels, pressure vessel such as hydrogen station, hydrogen power generation In.

Claims

1. a kind of high-strength simple-cutting copper alloy, which is characterized in that

Containing 75.4 mass % or more and 78.0 mass % Cu below, 3.05 mass % or more and 3.55 mass % it is below Si, 0.05 mass % or more and 0.13 mass % P below and 0.005 mass % or more and 0.070 mass % Pb below, and Remainder includes Zn and inevitable impurity,

As inevitable impurity the content of existing Sn be 0.05 mass % or less, the content of Al be 0.05 mass % with Under, the total content of Sn and Al be 0.06 mass % hereinafter,

The content of Cu is set as [Cu] quality %, the content of Si is set as to [Si] quality %, the content of Pb is set as to [Pb] matter When measuring %, the content of P being set as to [P] quality %, there is following relationship:

78.0≤f1=[Cu]+0.8 × [Si]+[P]+[Pb]≤80.8,

60.2≤f2=[Cu] -4.7 × [Si]-[P]+0.5 × [Pb]≤61.5,

Also, in the composition phase of metallographic structure, the area ratio of α phase is set as α %, the area ratio of β phase is set as to β %, by γ When the area ratio of phase is set as γ %, the area ratio of κ phase is set as to κ %, the area ratio of μ phase is set as μ %, there is following relationship:

29≤κ≤60、

0≤γ≤0.3、

β=0,

0≤μ≤1.0、

98.6≤f3=α+κ,

99.7≤f4=α+κ+γ+μ,

+ μ≤1.2 0≤f5=γ,

+ 6 × γ of 30≤f6=κ^1/2+ 0.5 × μ≤62,

Also, the length of the long side of γ phase is 25 μm hereinafter, the length of the long side of μ phase is 20 μm hereinafter, there are κ phases in α phase.

2. high-strength simple-cutting copper alloy according to claim 1, which is characterized in that

Also containing selected from 0.01 mass % or more and 0.07 mass % Sb below, 0.02 mass % or more and 0.07 mass % with Under As and 0.005 mass % or more and 0.10 mass % Bi below one or more.

3. a kind of high-strength simple-cutting copper alloy, which is characterized in that

Containing 75.6 mass % or more and 77.8 mass % Cu below, 3.15 mass % or more and 3.5 mass % Si below, 0.06 mass % or more and 0.12 mass % P below and 0.006 mass % or more and 0.045 mass % Pb below, and it is surplus Remaining part point includes Zn and inevitable impurity,

As inevitable impurity the content of existing Sn be 0.03 mass % or less, the content of Al be 0.03 mass % with Under, the total content of Sn and Al be 0.04 mass % hereinafter,

78.5≤f1=[Cu]+0.8 × [Si]+[P]+[Pb]≤80.5,

60.4≤f2=[Cu] -4.7 × [Si]-[P]+0.5 × [Pb]≤61.3,

33≤κ≤58、

γ=0,

β=0,

0≤μ≤0.5、

99.3≤f3=α+κ,

99.8≤f4=α+κ+γ+μ,

+ μ≤0.5 0≤f5=γ,

+ 6 × γ of 33≤f6=κ^1/2+ 0.5 × μ≤58,

4. high-strength simple-cutting copper alloy according to claim 3, which is characterized in that

Also containing selected from 0.012 mass % or more and 0.05 mass % Sb below, 0.025 mass % or more and 0.05 mass % The one or more of As below and 0.006 mass % or more and 0.05 mass % Bi below, and Sb, As and Bi Total content is 0.09 mass % or less.

5. high-strength simple-cutting copper alloy according to any one of claim 1 to 4, which is characterized in that

The total amount of Fe, Mn, Co and Cr as the inevitable impurity are less than 0.08 mass %.

6. high-strength simple-cutting copper alloy according to any one of claim 1 to 5, which is characterized in that

The Charpy-type test value of U-shaped recess shape is 12J/cm²Above and 50J/cm²Hereinafter, the tensile strength under room temperature is 550N/mm²More than, and protected at 150 DEG C in the state that load has the load of 0.2% yield strength quite at room temperature Creep strain after holding 100 hours is 0.3% or less.

7. high-strength simple-cutting copper alloy according to any one of claim 1 to 5, which is characterized in that

The high-strength simple-cutting copper alloy is hot-working material, and tensile strength S is 550N/mm²More than, elongation E is 12% More than, the Charpy-type test value I of U-shaped recess shape is 12J/cm²More than, and

675≤f8=S × { (E+100)/100 }^1/2Or

700≤f9=S × { (E+100)/100 }^1/2+ I,

Wherein, the unit of the Charpy-type test value I of tensile strength S, elongation E and U-shaped recess shape are respectively N/mm², %, J/cm²。

8. high-strength simple-cutting copper alloy according to any one of claim 1 to 7, which is characterized in that

It is used in running water pipe utensil, industrial piping-member, the utensil contacted with liquid or gas, pressure vessel and connects In head, automotive part or electric product component.

9. a kind of manufacturing method of high-strength simple-cutting copper alloy, which is characterized in that the manufacturing method is claim 1 to 8 Any one of described in high-strength simple-cutting copper alloy manufacturing method,

Include any one in cold working process and hot procedure or both；And in the cold working process or described The annealing operation implemented after hot procedure,

(3) maximum temperature reached is 525 DEG C or more and 620 DEG C hereinafter, and 575 DEG C to 525 DEG C of temperature region is kept 15 Minute or more, or

(4) by 575 DEG C to 525 DEG C of temperature region with 0.1 DEG C/min or more and 3 DEG C/min of average cooling rates below into Row cooling,

It is above-mentioned copper alloy is heated, is cooled down after, by 450 DEG C to 400 DEG C of temperature region with 3 DEG C/min or more and 500 DEG C/min of average cooling rates below are cooled down.

10. a kind of manufacturing method of high-strength simple-cutting copper alloy, which is characterized in that the manufacturing method is claim 1 to 6 Any one of described in high-strength simple-cutting copper alloy manufacturing method,

Include casting process；And the annealing operation implemented after the casting process,

11. a kind of manufacturing method of high-strength simple-cutting copper alloy, which is characterized in that the manufacturing method is claim 1 to 8 Any one of described in high-strength simple-cutting copper alloy manufacturing method,

Including hot procedure,

In cooling procedure after thermoplasticity processing, by 575 DEG C to 525 DEG C of temperature region with 0.1 DEG C/min or more and 3 DEG C/ Average cooling rate minute below is cooled down, by 450 DEG C to 400 DEG C of temperature region with 3 DEG C/min or more and 500 DEG C/ Minute, average cooling rate below was cooled down.

12. a kind of manufacturing method of high-strength simple-cutting copper alloy, which is characterized in that the manufacturing method is claim 1 to 8 Any one of described in high-strength simple-cutting copper alloy manufacturing method,

Include any one in cold working process and hot procedure or both；And in the cold working process or described The low-temperature annealing process implemented after hot procedure,

In the low-temperature annealing process, be set as following condition: by material temperature be set as 240 DEG C or more and 350 DEG C it is below Range will be set as 10 minutes or more and 300 minutes ranges below and when material temperature is set as T DEG C, will be heated heating time Between when being set as t minutes, meet 150≤(T-220) × t^1/2≤1200。